112: Building a BIG-POWER LS That Actually Lasts.

Speaker 1: 0:00

They say, oh, an LS will make 1,000 horsepower with the stock bottom end. Well, yeah, it will, but unless it's in a road car that just drag races occasionally, it doesn't last. Aluminium block LS in a proper drift application where the car is a fast car and it's got drip, I'd sort of shut it off at 800. Any more than 800 horsepower you're going to see all the main caps have walked around and it's going to have leaking head gaskets. You just can't keep the heads on it.

Speaker 2: 0:35

Welcome to the HPA Tune In podcast. I'm Andre, your host, and in this episode we're joined by Mitch Pullen from Pullen Spec Engines in Australia. We met Mitch, actually, at World Time Attack Challenge back last year 2023 and he came to our attention because he's really bucking the trend when it comes to engine combinations for drifting. His Nissan Silvia is fitted with an LS no big deal, you might be thinking. The part that is kind of a big deal, though, is it had a massive root style blower sticking out of the bonnet, and we obviously don't see that very often. In Mitch's own words, this is definitely not the ideal combination. If making maximum power was your goal. The root blower is somewhat inefficient and any properly sized turbo combination would easily make more power, but despite that, he's still making 800 horsepower out of his engine, which is obviously no joke, and it is a bit of a fan favourite and obviously has that look of the blower. In this interview, we learn about Mitch's background and, interestingly, how he learned how to race go karts and build kart engines at the tender age of just 10. He's also built up a fairly impressive skill set, understanding the skills of fabrication, a race car setup and as well, of course, engine building, which is his main gig we talk about some of the intricacies of the LS platform and some of its known weaknesses. We also talk about some of the clearances used inside an engine and how we may need to vary these from the manufacturer's specifications for a particular application, a particular fuel or a particular power level.

Speaker 2: 2:16

Before we jump into our chat with Mitch, for those who are new to the TuneIn podcast, high Performance Academy is an online training school. We specialise in teaching people how to build performance engines, how to tune EFI, how to construct wiring harnesses. We also cover topics on fabrication, 3d modelling in CAD, race driver education and data logging, just to name a few. You can find all of our courses at hpacademycom forward slash courses. All of these courses are delivered in high definition video modules that you can watch from anywhere in the world, provided you've got an internet connection. This means you can learn from the comfort of your own place and you can learn at your own pace. All of our courses also come with a 60 day no questions asked money back guarantee. So if you purchase them for any reason at all, decide it wasn't quite what you expected, no problem, let us know. We'll give you a full refund and for podcast listeners, you can also use the coupon code PODCAST75,. That will get you $75 off the purchase of your very first HPA course. We'll put the coupon code in the show notes to make it nice and easy for you to find. Lastly, if you like free stuff, then I've got a great deal for you.

Speaker 2: 3:26

We are constantly partnering with some of the biggest names in the aftermarket performance industry to give away some great prizes. You can always find our latest prize at hpacademycom forward slash giveaway. It might be an aftermarket ECU or dash, it could be some engine components or engine building tools, or just about anything in between. It could be some engine components or engine building tools, or just about anything in between. They are great prizes and we will ship them free of charge to your door if you're the winner. There's no tricks here. No purchase required to get your name into the draw. Alright, enough with our introduction, let's get into our interview now. Alright, thanks for joining us today, mitch, and as usual, let's find out a little bit about your background and specifically how you formed an interest in cars.

Speaker 1: 4:08

So I sort of bred into it, I guess you could say in a way. So we always had there's always been machinery in cars and race cars and all that sort of stuff around us and my old man raced stuff and he's done similar things to what I've done as well in his younger years. So where it probably started for me was obviously he was racing Speedway at the time when I was a little kid doing some Speedway stuff. So I was always at the races and doing whatever I could to help out and always around the shop. And back in the days I remember when he got the first dyno it was a Vane dyno, which is probably around 2000,. I guess I was probably five or six or whatever I was. So I was always around that and getting an idea of oh, why do these cars go on this thing, what's going on? All that sort of stuff. You know what I mean. So that just become normal for me to be seeing that sort of stuff. Then come to a point where I started racing.

Speaker 1: 5:00

Go-karts was probably when I first started getting involved with having to go faster in things. Go-karts was probably when I first started getting involved with having to go faster in things. So I was always being a bigger kid, I was at a weight disadvantage to all the other smaller kids. So the only way we could make that up is I had to work out how to Make more power. Make power exactly. And there's always a limit to that too. So the old man, he was always so busy at the shop and stuff he couldn't always just hold me hand and do everything. So I was sort of 10 years old having to understand how those little Yamaha J engines actually worked and how to move forwards and go faster with them. So that's where I first started being a two-stroke Obviously it doesn't have a camshaft but first started understanding, I guess valve events for a lack of a better term as far as Port timing yeah, exactly, moving barrels up and down and all that sort of stuff to change how it went and where it went.

Speaker 1: 5:50

There was rules on compression and stuff. There's like a little bubble test thing you put in the spark plug hole to measure that and you couldn't overflow it with a certain amount of liquid in there. So there was all that stuff and we had. I used to strap them onto the. We had a dyno dynamics dyno at that time, so I'd strap them onto that and just start changing shit and start learning. If you move the barrel up, what happens? If you move it down, what happens as far as? What can we do to get compression back in it if we've moved it up? And all this different stuff.

Speaker 2: 6:19

Yeah, okay, so let's just talk a little bit about that specifically. It's interesting to me because my background actually is somewhat similar. I actually started racing karts and we kind of had like a 50cc motor mower engine and yeah, same sort of thing. Like, obviously the drive for more power is always pretty key. We had a lot of controls. You mentioned there that you've got a sort of scrutineers checking the compression ratio of the engine. The port timing is quite critical and I do not make out that I'm an expert here on two-stroke engines, but the port timing is quite critical and big gains in power can be made by changing the shape of the ports. Do they check the port shape as well, make sure that they hadn't been modified, or is it just all down to this compression ratio, which obviously is also affected by the port timing?

Speaker 1: 7:11

Yeah, they would check. If you ran a state round or a national round or something like that and you go all right and you put it up the pointy end, then they'll be taking your engine off and they'll be looking at all that sort of stuff. So club stuff, stuff, you could give the ports a tickle and sort of get away with it. And then we also had a little I forget what it was. We had this, this fuel additive, and it was whatever.

Speaker 1: 7:33

It had a heap of oxygen in it, whatever it was I don't know if it had a bit of nitro, methane or some nitro or what it was. But what ended up happening is you couldn't get enough fuel in it after then because the drilling in the carburetor wasn't big enough. So you'd run your fuel. You got your two fuel screws. You'd have to the low speed one would only go quarter of a turn, then hit the high speed one. So you have to pull the high speed one out, put the low speed one in the wrong spot, then put the high speed one in.

Speaker 2: 7:58

That was worth about three horsepower on a 10 horsepower engine that was going to be the next question I was going to ask because you said you were running it on a dyno dynamic, so I can't imagine it was making much. So you're actually able to. I guess what I'm getting at is the dyno was sensitive enough to actually be able to register 10 horsepower and, more importantly, the microscopic changes you're obviously going to see with the modifications.

Speaker 1: 8:22

Yeah, they're a pretty good thing to use and back then obviously they had it half all right with the DOS system. It was an old DOS one and you could make a difference of half a horsepower and it made sense, like, where you're going. And another thing we used to muck around with too, obviously you got the stator which does your timing. So the first thing you do is pull that off, get rid of the keyway and start sliding that around, because that's like twisting your dizzy, I guess. So you'd make it when you're moving your barrel up and down, changing your port timing. Obviously you can make differences to that as well, but the fuel is what really helped it.

Speaker 2: 8:52

Yeah, so essentially a 30% improvement in power from the fuel. That's not small. How long did it take before people sort of noticed that your cart smelled a bit different when it was running?

Speaker 1: 9:06

Oh yeah, You'd have to sort of try and warm it up when no one's around and stuff. It definitely made up for the eight kilo disadvantage that I had. You just put your foot flat and drive past them Like three horsepower when you've only got 10. Oh yeah, Massive.

Speaker 2: 9:19

Huge.

Speaker 1: 9:20

Yeah, but then I struggled to finish a weekend without putting a hole in a piston. You just couldn't get enough fuel in.

Speaker 2: 9:28

Yeah, okay, all right. Well, that's an interesting introduction to engine tuning and what can go wrong when the fuelling isn't correct. I mean, that's also quite an interesting aspect of when you are in a control class, the ways we can maybe bend the rule book a little bit to our favor. Yeah, I think probably fair to say if you're regularly seeing the top step of the podium. People are going to be starting to ask some pretty difficult questions, though.

Speaker 1: 9:57

Yeah, definitely. And with the whole fuel deal there's bending the rules and there's blatant disregard at some point, isn't there? Yeah, yeah, 100%, yeah, definitely helped. I think that the whole the melding, the piston deal, it just oxy a hole in the center of it. I'm not sure I feel so much the fact that it was out of tune, but I don't think, whatever the fuel was that we're mixing, I don't think it mixed that well with the pump style fuel, so it was always changing, I guess.

Speaker 2: 10:24

Right, so not a consistent batch from one day to the next, or one session to the next.

Speaker 1: 10:29

Yeah, there was something going on. I don't know, I was a kid.

Speaker 2: 10:32

Yeah, fair enough. I mean, I'm guessing you weren't getting too granular with this with sort of exhaust gas temperature, or you can't really use a lambda sensor in a two-stroke engine.

Speaker 1: 10:43

Try and poke it in the best you can and get a bit of an idea.

Speaker 2: 10:45

All right, so I'm guessing, at this point you're also getting a fairly decent hands-on experience with how to rebuild these little engines.

Speaker 1: 10:51

Yeah, so we did plenty of them then. Even the ones before we were banging the fuel in were going pretty good. So there was other people at the cart club and stuff the next minute, you know they want engines built. So that's where my first engine building for people probably started was doing those. It was primarily Yamaha J engines and just had a fairly good idea of what worked as far as within the rules with the port timing and the ignition timing and obviously then where you run the fueling. That was about all you can do. Follow your ring gap. That's about it.

Speaker 2: 11:21

You're getting a really good baptism of fire here at a very early age. Does this progress into any formal qualifications in terms of engine building?

Speaker 1: 11:32

I probably don't technically have a formal qualification as far as engine building goes. I'd like a licensed mechanic and all that sort of stuff. So I just did the normal, went through TAFE and all that sort of thing. But as far as engine building qualifications it's pretty well just all on the job, training that I've been around and done, sort of thing.

Speaker 2: 11:50

Okay, every country has their own sort of rules and guidelines on what you can and can't do. In Australia, is there anything around the engine reconditioning trades that require sort of certain qualifications, or is it kind of a free for all?

Speaker 1: 12:08

So I'm licensed heavy vehicle mechanic. It's kind of funny how it works. So heavy vehicle covers cars, obviously all your plant machinery. You do a welding course as part of it, so you're somewhat certified for welding and part of it as well. Obviously you rebuild engines during that as well and you do some minor machining stuff, like you'll grind some valves and they get you on a flex hone and a bit of stuff like that. But legally wise I'm pretty sure it covers you. You're good to go to do whatever. There's obviously another engine machining reconditioners course as well, which then just makes your engine reconditioner.

Speaker 2: 12:44

Yeah, sure, I'm interested in your sort of take on the differences between your sort of average engine reconditioner and someone like yourself who's building very high spec, performance or race engines. My sort of thesis on it I guess if you like I'll put that to you is that there is quite a significant difference between the skill set required to just rebuild your average Toyota Corolla 1.6 litre four banger and then taking a production 350 horsepower V8 and building that to a specification where maybe it's making 700 or 800 horsepower. Do you agree or disagree with that?

Speaker 1: 13:22

Yeah, and it's a little bit like looking at an auto electrician compared to mil-spec looms and stuff. I guess as well, isn't it?

Speaker 2: 13:27

it's just yeah, I think that's actually a perfect comparison, yeah yeah, yeah, it's so different.

Speaker 1: 13:32

like an engine reconditioner to an extent, they're probably just rebuilding something to the book and the book tells you what clearances you got, your your bottom side and your top side, you've got your hone finish is just sort of whatever. Then you bed it in and providing you within sort of 10% or 15% of all that, then it's going to be no dramas, isn't it? Yeah, yeah, whereas when you're doing some of the stuff that we're doing, we're sort of operating beyond the envelope with a lot of things, especially when you're building something somewhat to a budget but you still want to make the big power same as the guys with the big budget. So I haven't always been blessed with heaps of money. We've got to spin things that shouldn't be spinning faster than they want to spin, if that makes sense. So then you're always, you're constantly learning, and what always makes sense and what you want to do you can't always do, because there's other reasons and impacts that become part of it, that just you get pushed to do different things.

Speaker 2: 14:25

Yeah, yeah, absolutely. You can't look up the factory workshop specification for a factory engine no-transcript. Yeah, now that's actually a really interesting aspect with the bearing clearances. But we'll carry on this conversation. We'll come back to some of the more specifics around the engine. So let's sort of fast forward how your sort of trajectory go from from this point where you're starting to rebuild these two-stroke engines for other carts so we've got the two-stroke cart stuff and everything that all went.

Speaker 1: 15:12

That went probably till I was sort of 14, 15 sort of thing. Then I ended up that big like I grew up fast, so I was just. I was that much too heavy that there was nothing. You just couldn't be competitive, if that makes sense.

Speaker 2: 15:25

Couldn't cheat enough.

Speaker 1: 15:26

You couldn't cheat enough. No, not without standing out. Yeah, I hate that. And you don't want to always just cheat either.

Speaker 2: 15:31

No, you can only do so much of that Sometimes It'd be nice to win on Mirrored alone.

Speaker 1: 15:36

Yes, oh, 100% yeah, which I did plenty of that too. But it's just fun when you make a kart go way faster than it ever should have. So then the next thing for me was I had like a little Corolla KE70 with a 4K engine and I started doing. I did a few motocarnas because it was the age to do a carna cross at the time, which a carna cross is like a real small rally sprint sort of thing, like a 30-second lap of the track. So I did a few motocarnners and I started doing carner crosses. So then I was in an environment where I didn't have any rules anymore and whatever my brain could imagine and whatever skills I could learn I could do to the car to go faster. So obviously there's a junior class in an outright and I didn't really care about winning the junior stuff, I just wanted to beat everyone. So that progressed. So standard engine for a little while. That's where I started learning about where to point your wheels to make things happen. So some of the first changes to that is obviously I'd lengthen lower control arms and I cut and shut the steering arms to give it more locks and when you flick it you can, you know, catch it, all that sort of stuff. Then it come to a point where it didn't matter what I did when you turn in and you were sideways, you had to keep rolling out of the throttle to not loop the thing, even with a heap of lock. And you can put a heap of lock on, but then it'd go around the corner slow.

Speaker 1: 16:56

So at this point we were involved with V8 supercars and stuff like that. So I'd be sort of still a kid laying under there having a look and thinking, well, why is there these two arms on the diff that mounted this centre point that goes up and down? What's that all about? So this is when I discovered roll centre. I thought, ah, so I had a panhard bar on that car, obviously. So I thought so if I move that panhard bar down, I'm going to have more rear grip. And then my driving style was rewarded with that, because I was happy to have a car that would push or understeer and then I could manhandle it through the corner. Then I could have more throttle commitment, be less sideways and have the thing when I have grip on the rear. So that's where I got a lot of car setup knowledge too, and I changed all that pnr bracket and then I ended up, more is better, so I'll give it more and more. And it got fairly long and then it hit the ground and tore off. So too far, too far, yeah.

Speaker 2: 17:47

So then I put a watts link in the back of that thing and then it was getting fast and then I just didn't have the power to to win yeah, it's always sort of uh, you go around in circles with these things, you, you have too much power for the car to put to the ground, and then you fix all of that and then all of a sudden you now need more power again. It's a vicious circle.

Speaker 1: 18:06

Yeah, develop the car to the point where then the engine was holding it back again. So it's not always. You can't always just throw power at things to fix the problem either.

Speaker 2: 18:13

I couldn't agree more. I've said this before on the podcast and it's worth repeating the number of times I saw customers come to me in my old shop and we used to run pretty regular track days. So it was just an enthusiast track day. It wasn't competitive but a lot of fun and it gave a lot of people their first exposure to driving on a racetrack. And for some the bug would bite pretty hard and you know we were in the business of selling modifications. So it worked great for us and without fail.

Speaker 2: 18:42

Every time it was like I need more power. And yeah, sure, that is one way of shaving lap times, no doubt at all. But I think that's probably the last thing you want to do. Particularly if you've got a car where you've still got relatively stock suspension and brakes, you start adding more power to it and you end up with this evil handling thing that's sort of just trying to chuck you off the track at every corner. So it's not maybe the most exciting way of improving lap time, but dialing in your suspension, getting your handling dialed, your grip and your brakes, then adding power is my preferred technique yeah, definitely.

Speaker 1: 19:17

Well, that's and that's the natural progression that this car took. So we had the as good as a Corolla could be, with some cut and chuck front end and a homemade Watts link in the rear, so I ended up with a full Watts link. After I broke the panhard off, just a series of holes drilled. I could move it up and down.

Speaker 2: 19:34

It's obviously difficult without the aid of graphics, but can you talk to us about the difference between the panhard rod? Both of these the Watts linkage and the panhard rod are both made for locating a live axle or differential laterally in the car, so side to side, so it's not just going to slide out the side of the car when you start cornering. But there are some fundamental and important differences between the way a panhard rod achieves this versus a Watts linkage. Panhard rod a go-to for OEMs because cheap and easy to produce. Watts linkage is a bit more involved. But can you give us a quick overview of the two?

Speaker 1: 20:07

Yeah. So a Panhard rod mounts to one side of your diff, your differential, so a live axle car, rear-wheel drive car. It'll mount to the diff and it's about 1,200mm long, whatever it may be. Then it mounts to the body of the car on the other side. Now, one issue with a Panhard bar is because it's always it's operating wish they could see this. It works through an arc. So as it goes through that arc the diff has to move. So the diff will move and the longer you can get the Panhard bar and the closer to straight you can have and all these things keep it as central as possible. But the diff will always move, sort of, let's say, 10, 10 millimetres sort of thing, from side to side through the arc, which is not probably always the worst thing in the world, but it's a bit of a drama. And then the drama that I ran into with the Panhard bar. So because my roll centre, I wanted it to be so low to put so much grip into the rear. So, as you put, if you imagine, I don't know if you have a Coke bottle sitting in front of you if you put your hand to the bottom of the Coke bottle and then push the top. The Coke bottle wants to fall over. So that's your roll center mounted low. So that's moving the Panhard bar down on the body, that's moving it lower. That's how the car wants to react. So the car, if you can exaggerate that and get that low enough, the car will want to tip over, even though it might not look like it wants to. Then if you, as you move upwards, you can keep pushing on the bottle cap of that, of that bottle, and you move your finger halfway up to the middle of it and push on the bottle cap, it's probably, it'll probably still want to tip over, but not quite. Then you exaggerate that again, move your finger up to the bottle cap and push on the bottle cap. The bottle's going to slide across the table if your other hand lets it go. So that's how the roll center and a panhard bar works.

Speaker 1: 21:46

And I probably didn't have any fundamental issues with the arc and stuff which obviously in circuit racing and more refined motorsports will become an issue. But my issue is the amount of grip that I wanted to put into the rear of the chassis. I just hit the ground with the bar, with the bracket, sorry. So how a Wattslink alleviates a few problems. One thing is I could then have my bracket still in a similar spot, getting it really low, because it's now in the center of the car, so the car's rolling over that center, so it never has a section of body that gets really low, it's on the bump stops and it can't really hit the ground.

Speaker 1: 22:22

Then the other difference is so how a Wattslink works. It's got two bars and they'll mount to the diff on each side, usually one mounted sort of on the bottom of the axle tube and one mounted on the top of the axle tube. Then you'll have like a rocker system in the centre which both of them will bolt to with the same distance between the centres as where they mount on the diff. Then in the centre of that. So that'll have three bolt holes and usually a nice bearing and stuff so it can run with no friction. Then where you mount, the second of that rocker arm section is where your roll centre's transmitted through the centre of the chassis.

Speaker 2: 22:56

Yeah, we might try and get a graphic into the show notes here, at least a link to something, because obviously it's difficult to visualise if you haven't seen a Watts linkage. But superior because with that sort of rocker system and the two arms going out to each side of the differential, we now alleviate that problem of the differential moving side to side during its bump and rebound travel. But you've also got the ability now by relocating where the Watts linkage mounts, you can easily adjust your roll center as well yeah, 100, yeah.

Speaker 1: 23:28

And then when you get into like the real race car stuff, you can. There's options where they have like a threaded section which can move it up and down from in the boot.

Speaker 2: 23:35

There's other options which just have a slot that clamp onto themselves there's there's a million different ways that engineers and people have come about making it easy to adjust yeah, and there's a local race class that I used to be a parity manager for here, which was the New Zealand V8 touring cars, and they were on a control chassis at the point I was involved and they had that adjustable linkage so you could basically adjust that roll centre height during a pit stop. I think it was through the rear Lexan window. So basically just put a socket down through there with an extension and wind it in or out a couple of millimetres, and that was enough to keep the driver happy or make them more angry, as the case may have been.

Speaker 1: 24:17

With the fuel load moving or changing and things like that.

Speaker 2: 24:20

Yeah, well, that's actually a really valid point, because a car the handling balance is not a static thing, particularly for endurance racing, where you might be burning off 100 litres of fuel during a stint. Obviously that does have an impact on the balance of the car as that fuel burns off. So it is always nice to have a couple of levers we can pull, essentially to sort of tweak the balance to our liking. All right, we've gone down a massive rabbit hole here, so let's pull it all back. So you've got this K70 to a point where it needs more power. This sounds like it's right up your alley. So how do we solve that? So we're back on the engines here.

Speaker 1: 24:55

So how I worked out to solve that. I was on the back of those days. It was YouTube, but you couldn't. Just there wasn't Instagram and stuff as much. So there, oh, there was YouTube, but you couldn't. Just there wasn't Instagram and stuff as much, so there wasn't. You weren't just flooded with ideas. So I was on forums and stuff trying to learn you know, how do we make a 4K go better, so you can put cams in and do all that, all those sorts of things. And then I obviously understood standalone computers and stuff. So I thought, oh, wouldn't it be? I'm going to inject it. Then I thought, well, that's going to help it a bit, I'll put a cam or do something. I thought, oh, that's not enough because I don't know, I had probably what, 50 horsepower, something like that, and there was things there with 200 horsepower. I was severely underpowered. So I thought, no, we need to make a big difference. So this is where I learned about Toyota superchargers the SC12 and the SC14. Yep, off the 4AGZE.

Speaker 1: 25:46

Yep, yep. And then the SC14,. Was that off the MR2, or something?

Speaker 2: 25:50

I'm struggling to remember. Yeah, the SC14 is bigger. I ended up messing around with one but never actually got it running. I think the AW11 came out with the SC12, which was the smaller of them, and I am struggling to remember where the SC14 came from, but let's just assume it did the.

Speaker 1: 26:09

SC14. One is bigger than an SC12. I think does the 12 relate? Is it 1,200cc per revolution or something?

Speaker 2: 26:16

I don't know off the top of my head. One of our listeners will know, though Someone will answer that question, I'm sure.

Speaker 1: 26:25

Anyway, so I got an sc14 blower at the time because I understood a bit about blowers. And one thing I had a bit of an idea on which I haven't changed my mind on this is if it's going to become inefficient, if you can have a bigger blower and spin it slower, then you're doing you're doing less work to the air to get what you want to happen. So if I can make, in this case it become 12 pounds of boost with a sc14 blower comparative to an sc12, I thought, well, that's got to be better. So we went the the sc14 blower and did a um, made up a drive to suit that. So there was all dry sump pulleys and everything everywhere around the workshop. So I had a series of dry sump pulleys. I made a little crank mandrel up. I had one it was actually an old water pump pulley on the crank mandrel. Then I could change the blower drive ratio by swapping dry sump pulleys on it. So that's how that happened.

Speaker 1: 27:10

Then at the same time we were a haltech dealer. So I was. I think I just left school at this point, so I only went to year seven at school. So then I was like sort of just turned 14, uh, which is when I should have been year eight, and then I was working. So that's how I started actually bringing some budget together to muck around and that obviously helped the evolution this is a very, very early start to a career in the industry.

Speaker 2: 27:34

It's impressive actually.

Speaker 1: 27:35

I definitely had a head start and because I was so driven in the direction I wanted to go, the fact I wasn't at school, I was still going forward, still learning. So it wasn't at school. I was still going forward, still learning. So it wasn't an issue. Put that long story short we put the SC14 blower on it and then I had an intercooler off an R33 or something like that, hung off the front. I've actually got some photos somewhere. I'll see if I'll send some to you. Then I had an intake manifold off a 7K off a Toyota Townace, and the port shape was slightly different on that. It was bigger and then had a funny shape. I don't know what it was for. It must have been to miss the bolts to bolt the manifold on, I think. So that's where my first taste of head porting come in, and, like many people that port their first head, I just made everything big.

Speaker 2: 28:15

Yeah, big is definitely not always better when it comes to porting.

Speaker 1: 28:19

Definitely not the answer. Well, I made it big and I didn't modify the manifold. Well, I made it big and I didn't modify the manifold. I just port matched the head to the manifold, but it was big. Then I bought a set of headers for it, a little set of four into ones, because it had this factory exhaust manifold still and just made the exhaust ports bigger. That all worked not too bad. I had some injectors. I had something that might have been some 300 or 400cc injectors. Then I bought a Haltech Platinum Sport 1000 for it, just with the flying lead kit.

Speaker 1: 28:47

What else we do then? A haltech dash, just a iq3. Back in those days, a dash put a clutch in, it did a couple of things like that that would obviously need, and we were running supercars at the time. So after each event there was always sort of 40 liters of E85 left over, because that's when they moved to E85. Now this is back. I'm 14. So what year would that have been? What's that? 2005, 2009,? This is so before E85 had become a big mainstream thing.

Speaker 1: 29:17

So I rented on E85 and then I had to do the loom. So I did all the wiring harness for that as well, which I was lucky because I was able to. Everything that I looked at was high quality race cars with high quality stuff. So to an extent I just copied what I'd been seeing. I've seen nice wiring. I learned where to buy that good stuff from. And then so here I am, 14 years old, making a Tefcel and Raychem and sort of booted loom for me Wow, paddock basher, you could almost say with a Haltech ECU. And another cool thing I put LS1 coils on it. So I had four LS1 coils mounted to the rocker cover. And then I got a distributor out of a Mitsubishi Magna which had like a 360 and four optical deal inside it. Then I got a guy to machine that to put my distributor gear and stuff on. So I had like full, like as good as today can be spark control and fuel control.

Speaker 2: 30:14

So you really turned the 4K into something pretty special.

Speaker 1: 30:17

Yeah, I made it pretty cool. And then that thing on 12 pounds of boost made like 120 horsepower, I think it was.

Speaker 1: 30:25

So you're over double where you started, yeah, to drive it was insane, especially for me as a kid. I thought, oh this, this is gnarly, uh. And then I started once I had that to turn into a bit of a weapon and it was fairly light as well. So then we started winning all the carna cross stuff and I probably did that for 12 or 18 months in that car like that and pretty well won everything I drove it in as far as it was. It was just perfect for car lacrosse size events, impressive, yeah.

Speaker 2: 30:50

So so that was my first real big deal into getting involved with cars, I guess you could say so you're you're doing the fabrication, the engine, the engineering of the chassis and the tuning and you're building the wiring harness and you're 14.

Speaker 1: 31:07

Yep, so the tune of that the old man gave me a hand. Obviously I didn't fully tune that one myself, but I did a fair bit of it. The wiring harness, I did the whole lot as far as all the hands-on stuff. So that's when I really started understanding how all that worked Just on that basis.

Speaker 2: 31:20

I mean, you said you're exposed to these professional milk spec harnesses from the Supercars series. Fair enough, but just seeing these is not always going to give you the insight into how to actually produce them. So again, the resources as you mentioned there YouTube, et cetera, the stuff that we sort of rely on today, hpa courses aren't there for you. How did you learn these skills?

Speaker 1: 31:46

So we would do the old man would do bit of wiring like just putting um ec using cars and all that sort of thing, just you know, general performance shop things that you would do, which is what we're running at the time. So not only did I see, I obviously knew what, what the top step, what good stuff was. I I had, like obviously seen a lot of it get done and I'd be crimping pins on and doing bits and pieces when the time come to wire it. I was fairly confident, as you are when you're 14 sometimes, and it all turned out great. I did a pretty good job and I'd always add, obviously, like read and study and learn anything that I could learn.

Speaker 2: 32:17

I would learn to understand what I was doing before I just did it and it sounds like you're in the perfect environment, though, to test and learn and expand your knowledge, though, particularly with your own in-house dyno. I mean, that's a dream for many budding tuners, and obviously it does significantly fast-track the learning curve. Yeah for sure. All right, well, you're 14. There's still a fair few dots to join here. But what happened after this? Obviously, now you're into drifting. How did the progression from so?

Speaker 1: 32:52

I wasn't quite into drifting yet, so I'm still doing that. Then that thing obviously I stopped doing the car. I thought I started, didn't circuit race, I did some sprint stuff and that and then thought, oh, it doesn't have enough power. So I put a turbo on it, made a turbo manifold and the turbo was out the bonnet and all that sort of stuff. So that's when I I put the turbo on it, then I made all the differences to make the tune suit the turbo. Then I probably only drove it four or five times once it was turboed and then it would just with a set of semi slicks on it. I just brake axles and didn't have enough brakes and we were beyond what that car was going to do for me.

Speaker 2: 33:27

Yeah, that's the again that normal cycle of add power, brake all of the drivetrain and slowly but surely find solutions for all of that. And that can get pretty expensive. I actually I had a KE70 myself which I bought with a Toyota 2T in it and we engine swapped that. We put a 4A GZE bottom end, silver, top 20, valve head and it was an old hand-me-down HKS GT30 off my drag car and of course the T50 gearbox and the factory differential didn't really like 200 plus horsepower going through it, so that cried enough pretty quickly.

Speaker 1: 34:10

Same as mine. Mine had a four speed. I remember I wanted a T50, I was like, oh, there they go, gearbox wise. Mine was a I don't know, someone will know I forget what it was called, it was a something Anyway. So that sort of just fizzled out into nothing, that car. I guess you could say Then at this stage we're in another shop and I'm a lot more, but when I turboed it I was like 16. So I was on my old plates then and that's when I learned how to TIG weld. So I TIG welded an exhaust manifold and stuff for it and then probably 17 is when it started fizzling out. So then I had my license, I was driving around, so I just had just a Hilux work ute that I bought when I was 17, like secondhand low case, which that ended up turbo'd too, and then there's a theme here.

Speaker 1: 34:54

There is. There is Make everything go better, learn what breaks. Then I had a circuit car. I had an improved production Commodore in amongst all this with an LS3. So I had an improved production Commodore in amongst all this with an LS3. So at this stage we're doing camshaft kits in LSs and I'm learning about valve spring setups, coil bind, lift to preload, you know, all the normal hydraulic roller LS stuff. I'm pretty well doing the engine building side of that. It's sort of 17, close to 18. And then we're also doing we were doing some. We had some GT4 Corvettes that we looked after that. We ran in the Bathurst 12 hour and that's where I got a good idea of keeping things reliable. Can't always just make all this power and hose everyone for two laps, because sometimes you've got to finish the race.

Speaker 2: 35:39

Yeah, it's hard to win if you don't make the finish line.

Speaker 1: 35:41

Yeah, definitely. So at this point is when I started getting exposed to like endurance, racing and and started getting excited about, hey, we can do these things, that at the end of 12 hours they still run great, and you haven't heard any parts and all that sort of thing, and obviously had the budget like was given the budget to help make all that happen as well. So did that. And then we did some just like improved production ls's and we're doing a few um development series, touring car engines as well so the development series, just for those who who don't know what we're talking about here.

Speaker 1: 36:12

So it's currently called. So the office got the main game v8 supercar series, then development series, which is now known as super two, which back then it was the fujitsu series and before that it was the Konica series, to ride around that era. So I wasn't entirely doing the builds but I had a fair bit to do with it. I understood what was going on.

Speaker 2: 36:31

For those who haven't followed the Australian Supercars series, it's probably. Well, it is. It's the pinnacle of motor racing in the Southern Hemisphere, I'd say. And that's a vehicle. And yeah, the super two or development series, is this the second tier, so kind of like a formula two, formula three, you know, finding drivers to move up to the main game yeah, definitely.

Speaker 1: 36:54

And and supercars back then, like the power they made and stuff was a pretty big deal because they're you're limited to a five liter engine, so they're like three inch stroke and four inch and whatever ball. Sometimes you'd go under-inch stroke to get a bit more bore size and unstrad the valves. The teams with more money would do that because they're happy to keep throwing blocks out because they were at their overbore on the first go. So there was that. And then you could only have 10 to 1 compression and back then they were on 98 fuel as well, before they moved over to E85, which E85 never helped for power because they weren't at MBT anyway. Like they were not. Like you're seeing a huge difference. They weren't knock limited, they weren't knock limited. Yeah, exactly.

Speaker 1: 37:33

So those things, five liters with 10 to 1 compression ratio and they're making like 640 to 660 horsepower, which was a pretty big deal. Yeah, that's impressive, yeah, definitely. And then another thing before rules come in, there was no rules on weights of components. So like you were seeing under 500 gram conrods, under 500 gram pistons, like everything was light, and then over time they bought in the 500 gram rule. It was called back then to stop people with heaps of money, just building things lighter and lighter, blowing everyone else out of the water.

Speaker 1: 38:04

Yeah, which it would. You could make the same power, but because you didn't have to accelerate the inertia the car would drive away.

Speaker 2: 38:11

Yeah, I think that's something that is so often just completely overlooked. You put a lightweight rotating assembly in an engine dyno before and after and, yeah, it's not going to show more power necessarily on the dyno, but it's no different essentially than removing weight from any other area of the car.

Speaker 1: 38:30

You can accelerate the engine quicker, so it is going to actually be faster on a racetrack yeah, maybe if you make if you like back, mill your diff gears, if you gun drill your axles, put light wheels on light tail shaft, all that stuff adds up and that that's what makes a well-built race car fast. It might not look fast when you look at the numbers like you think, oh, my car's got 800 horsepower or whatever, I should hose that. But when you get a well-built car that not only handles but it's got lightweight drivetrain, low inertia, like carbon clutches and stuff, they're fast without looking fast like australians, uh touring cars that they're fast for what they are yeah, I couldn't agree more yeah, so at this point we're doing engines and stuff.

Speaker 1: 39:11

So I'm being fairly well absorbed, like I'm absorbing all that information, and we're doing a few runs in that improved production car that I had. I bought that car myself. I didn't really have the budget to run it, so I just ran a few rounds here and there, sort of thing, the close ones.

Speaker 2: 39:25

Give us maybe a quick insight into the modifications allowable and improved production. It's kind of a bit of a hint in the name, but yeah, just lay that down for us.

Speaker 1: 39:35

So it's based on production. So the car I had was a VY Club Sport which was still sort of fairly modern back then. Engine could only be six liter and apart from that it was pretty well free. You could run a muck with the engines, providing you kept the capacity, so it had like more power than a supercar. Gearbox was pretty well free, so there was plenty of them with sequential hollanders and all that sort of thing. Rear end I'm not 100 sure, mine was just irs, but you might have been able to put like a live axle in it, which a live axle back then was probably better than the factory.

Speaker 2: 40:08

IRS. Okay, so it's counterintuitive, but more along the lines of the factory. Independent rear suspension was just poorly designed for a race application.

Speaker 1: 40:17

Yeah, in these days you'd have rocks in your head to be doing that, but back then it made sense. At the time you could have some little aero things. You could have a wing. Had to fit inside a certain size box, otherwise you could have a factory wing. Anything factory was fine. Obviously Still had to have glass, wind up and down windows. Brakes were pretty well free, suspension was free to a point, so pretty well, just production. Cars improved, I guess.

Speaker 2: 40:44

Yeah, okay. Well, it doesn't sound like there's actually many rules there, less than I would have assumed.

Speaker 1: 40:50

Yeah, there was a nine inch rim rule and you had to run a semi-slick tyre, so like a Yokohama AO50 was all the rage back then.

Speaker 2: 40:58

And that kind of becomes a limiting factor when you take engine regulations out of it. I mean you said there's six litres the limit, but there's still a lot you can do around that. But ultimately when you're limited to a certain tyre size, there is a limit to how much horsepower you're going to be able to put down through that tyre and otherwise it just becomes a little bit pointless.

Speaker 1: 41:19

Yeah, and even if you can put the power down for a few laps, you'll end up you'll cook your rear tyres and you won't be able to put it down later. And there was there's probably a weight rule too. They they were never light, they were a heavy car, so that the fact they're a heavy car that also cooks your tires and makes all that power that you made, that helped you for the first three laps. Well, it's no good when you got greasy tires and everyone's driving past you at the end of the race. No, no, it's not much fun. Yeah, so that was pretty well done.

Speaker 1: 41:44

I didn't really do a lot with that. We had some old. We had an AU supercar at the time too, which I did a few laps in that, but not many. Then I had a bit of a break from much motorsport stuff, just was just working and doing, you know, building the engines and running the shop. Oh, not running the shop, but a fairly big part of it. So this is where I've got that Hilux that I've bought. I'm on my P-plates, I'm driving around, I'm thinking, oh, you know, I haven't been on a racetrack for a while. Wouldn't it be good if this Hilux went better?

Speaker 1: 42:16

So there were some guys in Australia doing turbo kits, for them had a little manifold and you put like a Kenyagawa on it I forget what size and they had a little water to air in a cooler and stuff. So I put all that on it and they were a funny injector at the time on the 2TR with the long snout on them and stuff and it was a little bit hard to swap them and that. So how I tuned it, I just put a big fuel pump in it and wound the fuel pressure up. That in it and wound the fuel pressure up. That's one way of doing it. Oh yeah, worked for a while. So I'm like that thing was on eight or 10 pounds of boost, I don't know Laughed for a fair while on that and I thought, all right, let's make this number bigger on this dyno screen. So I ended up at wasn't that much, I don't know 16 pounds or something like that and just wound the fuel pressure up and the fuel trim's, just got all the other stuff to lambda one.

Speaker 2: 43:10

All the part throttle just seemed to sort it out. I thought, oh god, these new cars, isn't the knock control? Great, yeah, I think what you're describing there is absolutely not the way to tune an engine, but definitely not. Yeah, there's things that you know. When you're limited to what you've got available, sometimes you have to do what you have to do to make things work. I'll just reiterate a story that I have told before on the podcast.

Speaker 2: 43:29

But back in the very early days of my tuning I had a friend and customer who had an EK Honda Civic B18C, put a turbo kit on it or built a turbo kit himself, and we tuned that essentially by adding an extra injector that was run off a Hobbs pressure switch so it came on on positive boost. We tricked the map sensor so it didn't see positive boost. Pressure caused problems with the ECU and then obviously the thing would want to knock with 5 psi of boost. So the way we got around that was just to retire the base ignition timing. Obviously that's going to dull everything off boost, but you know it, it got the job done. It's not pretty. Would I recommend it now? Absolutely not, but you know. Just pointing out that there are various ways that we can get the job done. Some of them just are not as pretty as others.

Speaker 1: 44:17

You do what you do with what you've got, don't you? Absolutely yeah. So like I looked at, I wanted to put a piggyback in it and all this different stuff. I'm thinking, oh, it's a new Toyota, it's not that. Back then it didn't look that easy to do that, you know. I thought, oh Dash is going to do weird stuff, like all the different scenarios you know. Now I just plug into it and tune it Like it's no big deal. Anyway, it made 400 horsepower, it did it and it lasted about 12 minutes after that. Okay.

Speaker 2: 44:48

It didn't make it home. Are we talking here, though, power-related component failure, or is this a result of the tuning solution that's maybe subpar, I think?

Speaker 1: 44:56

if I had have treated it differently, it could maybe still be going. So we lived on a farm back then. It was sort of a farm out of town a bit. So I'm up this back road now I'm, I'm up the thing. So duty cycle where, as far as engine load duty cycle, I'm holding it flat and it's getting to the point where it doesn't want to push through the wind anymore and it's it's no longer accelerating. So it's not all that stress that goes, hey, I want to wreck you, it's it's not getting out because it was pulling timing. I think the timing was probably I don't know if it was perfect, but it was dealing with that to an extent. But I think what happened is we just got to the point when you've got lightweight cast pistons that are designed for fuel economy, with tight ring gaps and all the different stuff, like Toyota has done a great job of that and not a heap of boost.

Speaker 1: 45:40

Not 16 pounds of boost. That's not properly in tune and held flat for 45 seconds without just accelerating through it Because, like any normal scenario on the road, you put your foot flat and it just spins the tyre Like a single wheel of diff aluminium tray back. Spin the wheel, it's not under load.

Speaker 2: 45:56

This is something I do quite often talk about, as well as tuning for and, for that matter, building an engine for an application. And if you're talking, a street car that's never going to set foot on a racetrack. Well, if you value your license, it's pretty difficult with a powerful engine to stay at wide open throttle for more than, let's say, 10 seconds. You're going to be pretty damn fast. So that sustained high load for a road car is difficult to achieve, I mean not impossible.

Speaker 2: 46:26

There are some customers that I was a bit more wary of because I knew they had a pretty heavy foot. You know, you take it to the other extreme. I was involved in some land speed record tuning and there you're a wide open throttle for literally minutes and the particular engine I was tuning that was, I think, 1100 horsepower. So you have to sort of think about the load on that engine and what that sustained combustion temperature is also going to do to the engine components, the thermal stress on the pistons, the valves, et cetera. It's just a different ballgame. So you agree here that the tuning strategy and the engine building strategy would be vastly different between those two applications.

Speaker 1: 47:03

Oh, without a doubt, without a doubt, absolutely without a doubt. So, and that's like a lot of things too, like when you're building LSs and stuff, everyone goes oh you know, a stock LS does a thousand horsepower, no worries. Well, it probably does, I mean, I've seen it. It does it For how long and under what duty cycle. And that's where, like even the difference between, like a burnout car and a drift car, like, unless you've been in a fast drift car, it's hard to fully understand the fact that, like my Silvia makes 800 horsepower and there is plenty of times when I'm like God, I wish I had another 80 horsepower, but my foot is flat and the thing is almost steady, stating itself because it just when it's gripped up and it's fast, you can't just drive through the grip anymore. So a drift car is fairly loaded and sort of sustained load to a point.

Speaker 2: 47:51

I think a lot of people who haven't been involved in drifting and kind of looking from the outside think, well, it's just all wheel spin. But it's been this iterative cycle of people tuning more grip into the chassis, so then you need more power to overcome the grip so you can still slide it and it goes round in circles. And now, as you say we've got, if you look at Formula D in the States, a thousand plus horsepower is kind of like the entry level.

Speaker 1: 48:15

Yeah, definitely. And once you've got a big tyre on it and then go onto a track where the car speed's fast, it takes a lot to overcome that tyre and to keep the car sideways and to keep it making smoke and all that sort of stuff to keep it exciting for the fans. I think that's probably a common misconception as far as drifting, that everyone just thinks that you do something to have no grip on the rear and you're just sliding around. It's not like driving your Commodore in the wet, is it?

Speaker 2: 48:40

These engines actually are under a high level of stress for the lap. Yeah, they're under stress, All right. So on that note, what are you doing differently inside the likes of your LS and your S13? That makes it live so there's a few enemies.

Speaker 1: 48:55

One enemy is if you spend a lot of time on rev limiter, which is not good for anything but makes fire, so I do it. So valve train, and we're doing the revs too. It's not good for anything but it makes fire, so I do it. So Valve Train, and we're doing the revs too. We're not lying, it's doing 9,000 revs.

Speaker 2: 49:08

So it's, up there.

Speaker 1: 49:09

It's up there especially for a pushrod V8. It's spinning Valve. Train is a massive killer so it's solid roller. I mean it's got like Jezel rockers and all that stuff, all pretty good gear and pretty good gear, and put a lot of effort into the cam lobe to really soften that up, because being boosted still needs to make power but we don't need to rely on smashing that valve open and closing it fast to make the power.

Speaker 1: 49:32

So I'm probably throwing away I don't know you can measure it put a different cam in, but maybe 50, 60 horsepower of just outright grunt by making the cam softer and then so what that does is make them valves and the rockers and the push rods, everything's just on an easier ride, like if you go over a lazy bump, it's comfortable. If you go over something that boots you, it's not comfortable. So that's one big killer. Another thing I did on that engine to combat that without just having heaps of money and putting titanium valves and all that stuff, which is that's the correct way to do a lot of this putting titanium valves and all that stuff, which is that's the correct way to do a lot of this. I've run an LS1 head on it which is smaller, port, cathedral, port thing, and it only has a two inch and 80 intake valve, whereas like a standard six liter rectangle port is two and 125. And then LS7 is 2.2.

Speaker 2: 50:18

Okay, so you're doing this just to get weight out of the valve, essentially without going to a titanium material.

Speaker 1: 50:23

Exactly so it's got a Faria intake valve, a hollow stem intake, so it's still a high-quality, good valve. But then I just thought, well, why not make it even easier on the valve train? If I don't need the valve size to make the power, I'll just make the valve smaller. So that's how I helped that. And then also the exhaust valve smaller, like the exhaust valve is 1.6, which is the same as a six liter exhaust valve, but it's obviously the whole valve smaller and it's an Inconel exhaust valve.

Speaker 1: 50:49

Then we're running a good quality PSI valve spring. So it's a good, good brand, good quality valve spring. And you got to set them up close to coil bind as well, which what that does is if you get a, there's harmonics, doesn't matter what you do, there's harmonics and everything. So if you get a valve spring and you let's say this is common you get a valve spring for 650 lift, that's a common ls valve spring. Then what everyone does, they get a 650 lift or 675 lift spring, because that's good, and they run a 600 lift camshaft with it. Now what happens with that is you end up 140 thou or whatever the number may be, from coil bind, depending on how everything's set up and their installed height and stuff that gives room for the spring to oscillate and it goes crazy. If you look at any videos on YouTube of Spintron stuff, you get an idea of what that does it's pretty scary stuff.

Speaker 2: 51:40

A lot of things happening in there at high RPM with the harmonics that you would not believe until you see it.

Speaker 1: 51:46

It goes mental and what happens is so, when it's going mental, in there the center of the spring I guess you could call it it's shaking up and down. So in one application of the rocker opening the valve, the center of that spring feels like it's going up and down 20 or 30 times. Because it has it's gone up and down 20 or 30 times because it has it's going absolutely crazy, and that's why then you get them glowing red and all that stuff happens. They get hot and it's just stress on the spring and springs break, that's nothing.

Speaker 1: 52:10

Good can happen nothing good happens, no. So if you're only doing six and a half grand a street car, you get away with it pretty well. It's still not right. You get away with it. So we stack them springs down, and what stacking the spring does still goes crazy. There's nothing you can do about that. Well, maybe there is, but all different springs have different natural frequencies and stuff like that. So if you spend a lot of time on a Spintron and have enough of the right people, you can do things to do the best you can to have the spring not operate in that frequency range.

Speaker 1: 52:38

But what you need to do as well is if you get that thing stacked down close towards coil bind, well, all them coils going crazy in the middle, they all sort of they don't fully touch each other because it's not like it's getting coil bound. Now coil bind is when the spring's squashed and it can't go any further. But as they're doing that bounce, they touch each other and that just dampens all the craziness out. So then what that in turn lets the spring do is, every time it goes up and down, instead of, as it's, re-closing the valve which is opening the spring, instead of just sitting there dancing out of control. It's then had that little touch and then the spring. It takes a whole lot of that energy just gets absorbed into the spring, I guess, but it sort of goes away. So that's a big part of keeping valve springs alive Interesting, Especially when you'd want to drive things on the rev limiter and drive them like. The rev limiter's not good for anything, is it? It's just banging and smashing.

Speaker 2: 53:28

No, no, no. We want to stay away from it wherever possible. But yeah, unfortunately it is a necessary evil. Just in terms of stacking that spring, as you've mentioned there, I get the concept of getting it close to coil bind to limit the amount of spring movement. Are the negatives coming from this in terms of obviously, if you're stacking it that close to coil bind, the base spring pressure and the pressure over the nose of the cam are going to be increased from where they necessarily need to be to control the valve train. Are there downsides from that?

Speaker 1: 53:59

Well, if you get a spring that's got the correct pressure at 140 thou of coil bind, then it's probably the wrong spring. You've obviously only got so many options, so sometimes you've got to trade something off. You can't have everything perfect, but what you do, you try to go and I put a lot of effort into your seat pressure kind of sometimes just ends up what it is. It's not a lot you can do about it. It's more important to have it close to that coil bind than what the spring pressure number is. But you always put as much effort in as you can when you're developing something and thinking about this engine you're going to build to make sure there's a spring somewhere close to what you want to do. That's going to be close to the numbers you want, like close to coil bind and a PSI spring, because they're going in racecars all the time. Usually whatever lift they're rated to is between 50, 55 from coil bind.

Speaker 2: 54:47

I just wanted to take a moment out of our interview with Mitch and talk about a package of courses that are going to be perfect if you're interested in engine building and you're enjoying our chat, and that is our engine building starter package. A lot of enthusiasts think that building their own engines is something that's completely beyond them, but the reality is that if you've got an eye for detail and a little bit of patience, you absolutely can do a great job of building a quality, reliable engine, and this engine building starter package is the best way to do that. This package deal is normally $299 US dollars. You can use the coupon code PULLEN50, which is P-U-L-L-E-N 50, and that'll get you $50 off. Bring it down to just $249 US dollars. As usual, you're still protected by our 60 day no questions asked money back guarantee. This package includes our engine building fundamentals course, which, as its name implies, teaches you the fundamentals of engine building. You'll learn about all of the internal components in the engine. You'll learn about the typical engine machining processes that are required when we're building a performance engine, which is important because this will allow you to speak the same language as your machinist. You'll also learn about the clearances and tolerances inside the engine and understand how these may need to be adjusted for a given application.

Speaker 2: 55:59

Moving on from this, we're also including our practical engine building course, and this builds on the knowledge taught in the fundamentals course. This time we break the entire engine building process down into the HPA 10 step process. We know it can be daunting when you receive all of your machine components back from the machinist. What should you do first and what order should you progress in? By breaking this down into a 10 step process, each of those individual steps is quick and easy to complete and in no time you've got a completely built engine and you're going to have the confidence that when it comes to start that for the first time, it's going to produce great power, great torque and, most importantly, great reliability. This particular course is broken into two sections. The second section is our engine building worked example library and this is an informal walkthrough of that 10 step process where you can watch it being applied on a range of different engines.

Speaker 2: 56:49

I should have mentioned all of these courses are generic, so it really doesn't matter what particular engine you want to build. For the LS fans, you will be pleased to know that there is a full LS worked. Example, building up a stroked LS1. We're also including our how to degree a cam course, and this is probably one of the more common upgrades people make when building a performance engine. But it's only going to give you the power and torque increases that it's possible to achieve if it's degreed or dialled in correctly. Get this wrong, and not only may you not make the power the cam can provide, you could end up with expensive engine damage.

Speaker 2: 57:25

This course teaches you how the cam works, how cam timing works, and then introduces another step by step process that you can apply when degreeing your own cam. And again, this is generic. It doesn't matter if you're dealing with a pushrod V8 or a quad cam V12 or anything in between. As part of this package, we'll also give you 24 months of gold membership, which gives you access to our weekly live webinars, our archive of over 350 hours of existing webinar content. Plus you'll get two years of access to our private members only forum. So remember the entire package deal there with this particular special $249 US. Use that coupon code, pullin50, and you'll find that in the show notes. Let's get back to our interview now. Just coming back to the head choice, the Cathedral Port LS1 head. Obviously you've explained why you've gone that route and it makes sense. My understanding though, in terms of the actual port flow, quite a significant drawback over the later rectangle port.

Speaker 1: 58:22

So of LS3 style head, yeah, I think mine flows, it's a bit over 300, 325, 330, something like that, the LS1 head, whereas a rectangle port you'd be sort of 360 to 380 with a big port. Definitely a lot of things that hold it back, but for a purpose. For a purpose. So if you're building it as a probably still makes enough power in a competition drift application because you can sort of add boost. But if you're building an engine to make power and go fast, if it was a drag engine or something like that, there's some cathedral, there's some big cathedral ports out there and with a big valve and stuff that you wouldn't have a factory LS1 head, yeah, okay.

Speaker 2: 58:57

All right, let's talk about the rest of the engine combination. Is there anything sort of particularly special going on there? I mean 800 horsepower from an ls is is not out of the ballpark, but I mean it's.

Speaker 1: 59:07

It's a decent hit out yeah, well, it's 800 horsepower and I've just I've just had it apart giving it a freshen. So it's done a whole season last year and it's pretty well. It's back together now, almost exactly the same. I coated the skirts on the pistons. Same pistons are back in. It did a few little things but it works. So a lot of 800 horsepower ls. As you pull apart you go oh geez, this doesn't look real good. But that thing's pretty good and a lot of the reason of that is it's running a dart block, so a dart ls, next cast iron block. So the block's stiff, it's rigid, it's got stiff cylinder walls. The main tunnel doesn't want to swing around in it like it's staying where it is.

Speaker 2: 59:42

Give us an idea of the difference between that LS Next cast iron block and doing all of the usual upgrades to a factory alloy LS block in terms of adding sleeves etc.

Speaker 1: 59:57

Well, you add sleeves to an alloy block and it gets the bore rigidity pretty well there. That's pretty good, probably two of the biggest things to compare. There's obviously a pretty good, but probably the two of the biggest things to compare. There's obviously a lot of difference, but two of the biggest things of what you actually see is, even with main studs, the alloy block stuff, if you, if you rev it and make power, the main tunnel walks around, doesn't matter what you do. It just you can see it's always black between the caps and the block because they've been shuffling, threading. And it doesn't matter what you do with a four bolt LS block. The deck surface just moves around. It's just weak. They're not made to make 800 horsepower, it's factory road car stuff.

Speaker 2: 1:00:33

Yeah, I mean, I think the thing is, when you've got the engine block sitting there on the workbench or on the engine stand, it all looks solid and you sort of think to yourself well, obviously it can't move around, but between the crankshaft and the block itself, you know, 800 horsepower, 9000 rpm, as you mentioned earlier things are moving around like a noodle. So then you start beating up on your bearings and you have to increase your bearing clearance to try and make the thing live. And this has got all of these ugly knock-on effects right.

Speaker 1: 1:01:00

Yeah, another huge difference, which is a massive help in the dark block and other aftermarket blocks as well, is the priority main oiling. So on an ls, on a fix right. Yeah, another huge difference, which is a massive help in the dart block and other aftermarket blocks as well, is the priority main oiling. So on an LS, on a factory block LS, it feeds the lifter galley first, then, once they get all their oil oh, this sort of goes everywhere, but the lifter galley is the priority, I guess you could say Then from there it goes down to all your mains, then from your mains through the crank gets to your rods. Now another thing that happens with that aluminium block LS, especially if it gets hot, is obviously it grows, as you can imagine, and then you lose a whole lot of oil through the lifter bores. So, especially with solid roller stuff, and that you end up you're just bleeding all this oil off and you get to the point you can't get enough oil back into the thing. You just can't get enough oil pump to keep oil pressure, whereas with the Dart Block you've still got oil pressure.

Speaker 1: 1:01:44

But I mean there's a noticeable difference With the Dart Block.

Speaker 1: 1:01:48

One thing is that it's cast iron, so it doesn't grow anywhere near as much, and even the main bearing clearance, everything it stays a lot closer to where you've set it.

Speaker 1: 1:01:57

So you end up with just better oil pressure as well, which helps keep the engine alive, because the crankshaft sees not only better oil pressure, but the crankshaft sees it before the camshaft and lifters and stuff see it. And you've also got the option with the dart block to restrict the oil to the top end. So there's a little thread in there and you can restrict that galley. You can run like only a 40,000 or 50,000 RFS to the top end if you want so, then you so it's not just pumping all of the oil up top, exactly, so your crank really gets looked after and then you can. In a naturally aspirated application you end up being able to make more power because of that too, because you can run less gallons per minute of oil flow and still have the pressure that your bottom end needs and don't have all this extra oil leaking down, creating windage from the top. Yeah, yeah, yeah, that all makes perfect sense.

Speaker 2: 1:02:44

Yeah, so that's another big difference, just also in terms of you know, if people are looking at starting a build, what's a rough idea on the cost difference between buying a quality aftermarket block like this Dart LS Next and going through the sleeving process because that in and of itself is not cheap. The Dart block's probably cheaper, to be honest. Okay, yeah, well, that is kind of what I wanted to get out there. It's's actually a viable option.

Speaker 1: 1:03:05

Now the Dart Block also, depending how far you're progressing with the build, it has the option for six bolt heads. So that's, if you're not familiar with an LS, they've got four head bolts per cylinder, whereas, like the aftermarket LSX stuff, which is made by GM and then all the aftermarket stuff now, it's very common to have six bolt heads. So there's an extra head bolt at the top and bottom of the cylinder. So that's another plus for the dart or any aftermarket deal really. But a dart block is probably uh, there used to be sort of just under four grand. It's probably gone up a bit now, so about four grand and sleeving is about four, four and a half. So you're sort of similar money. But where you get penalized for the dart is if you're trying to build a car to go fast. You're like 45, 50 kilos heavier.

Speaker 2: 1:03:46

It's it's dense, yep yeah makes sense, okay, pistons, and specifically what you're doing with a high-powered drift engine to to keep those pistons alive, in terms of pistons of cylinder wall clearance, etc yeah.

Speaker 1: 1:04:01

So pistons, it's just got a shelf cp bullet piston, which is they're a good thing, there's nothing wrong with them, but they're still a budget friendly piston. Then we've got a pin upgrade. It's got like a 220 wall pin and they come with like a 180 wall pin as standard. So and it's common to see you see flex and they get pin galling and stuff from the pin flexing. So that pin being stiffer also helps with the rigidity of the piston, sort of just stiffens all that up. It's got a 6.3 inch callies conrod still nothing special, just a shelf conrod. Now usually if you try and do 9 000 revs with a standard stroke crank or a uh like a four inch stroke crank, which is common in an ls, the piston speed is going to be astronomical and then it wants to throw it all out sort of thing. So it doesn't have the best crank, definitely, but it's a factory GM cast crank shaft. It's a cast crank. Okay, it's a cast crank.

Speaker 1: 1:04:53

Yeah, did not see that coming at all and that's one of the updates for later. It needs a good crank in it. But how that works is it's a three and a quarter stroke or close to it's. 3.268 is the stroke and you get away with it because it has no stroke. The rod journal then becomes a lot closer to the main journal. So you've got that overlap for strength. You've got a whole lot of overlap and a heap more cheek. Yeah, yeah, that makes sense and then you can do the maths on it. But a three and a quarter stroke crank doing 9,000 revs is like a standard one doing. I did, I had it worked out. It's significantly different. It's like nearly a thousand RPM different. So it starts being a little bit less scary. I guess you could say yeah, yeah, sort of.

Speaker 1: 1:05:33

So, you got that. Then we run a bit of extra piston to cylinder wall clearance. It's about five and a half thou, that's quite loose, yeah, yeah so. So it was a little bit less than that. Before it didn't have it wasn't bad scuffing or anything, but just marked up the skirt a little bit last time. It's a tough one too to work out when it actually happened, because that piston definitely wouldn't be happy in there when it's on the rev limiter and it's making no cylinder pressure and it's bouncing around and everything happens. So it's just engine abuse, probably a bit of that, just to what you're seeing, not necessarily a problem as such. So I've got a coated cylinder, like the skirt of the piston is coated now.

Speaker 2: 1:06:11

So this is an anti-friction sort of coating.

Speaker 1: 1:06:14

Yeah, what's the blue one called? It's like a Teflon coating. So also there's a place in the States that do a. Have you seen those abradable coatings?

Speaker 2: 1:06:23

Yeah, yeah, I think JE are actually doing their Ultra Series. I think it is pistons and those skirts have that abradable coating and the idea behind it is you can run them with piston distensible clearance, more in line with what you'd expect to see on a factory cast piston, so it gets around that sort of noisy piston slap when the engine's cold, which is so prominent if you've got loose clearances with it. With a forged piston yeah.

Speaker 1: 1:06:48

So that would be a great option too, but I don't think anyone in australia is doing it. I think that's a. There's that line to line in the states are doing that. So with the clearance and stuff we've got a bit of extra clearance. So when it's because you don't know, sometimes when you're at a drift demonstration event you don't always get all the time to warm it up the best you want either, and if the cast block doesn't have the time to get all the water tempered and grow well, the piston is going to grow fast on the block once you've got your foot flat and the cylinder temps, whatever it is, egts are a bit under 800, so, whatever, the cylinder is pretty hot in there. So that's why I run a bit of extra clearance too, just to band-aid the fact of there's definitely times when the engine doesn't properly get to operating temperature and then it has to perform too.

Speaker 2: 1:07:27

Yeah, yeah, let's just talk a little bit about the differences with the likes of pistons, the cylindrical clearance between a factory cast piston and the likes of aftermarket forged pistons. And there's two typical materials we see with forged pistons. But the top shelf, the strongest, is the 2618 alloy, which has a higher thermal expansion coefficient than a cast piston. Hence we need this larger piston assignable clearance. So I think where I'm going with this is a lot of people building a mild to even moderately modified engine with more power than stock think that one of the first essential modifications is to jump to a forged piston. And I mean in some cases you know there are engines where genuinely the factory pistons are known to be basically made out of glass and you add another 50 or 60 horsepower and you risk losing the piston. Clearly in that case you've got no option.

Speaker 2: 1:08:30

But I mean I've taken and we're getting away from LS here. But 4G63 Mitsubishi I've made, I think it was about 800 horsepower on a stock short block. For a guy who had dreams of beating the stock block world record. We didn't get there, but the engine held together. And again, that's on a factory cast piston. There's some special tuning bits that I did in there to try and keep the engine alive in terms of manipulating the torque curve and reducing the peak torque. But yeah, what's your take on this? Forge versus cast? And is forged always a superior option?

Speaker 1: 1:09:05

Well, a lot of the stuff I do is usually a competition engine so I mean it goes the way of forged makes sense. But for a street engine, most street stuff especially if it's getting driven all the time because no one probably thinks about either the fatigue like a 2618 can handle less heat cycles than a 4032, which is the other common forge piston, and then obviously a cast piston. Well, they're probably good for obviously a lot more heat cycles again. So any street car that's seeing a lot of drive cycles like a lot of heat cycles and stuff like that, and on the street you're probably, even if you make big power, you're never actually using the big power.

Speaker 1: 1:09:43

In most street street applications cast is probably fine, like an LS with a camshaft and that if you want to give it a refresh and a rebuild, you've probably got no dramas. Just running a five-thousand oversize hypertechnic or cast pistons probably fine, whereas something that's copping a decent flogging and needs that extra safety margin I guess and the extra strength and the sort of if you think of the pistons a bit softer, I guess in a way you can give the thing a bit of a rattle, not that you ever want to, but they can see a bit of a rattle or ping or detonation, and then you can still drive after it, whereas you get a cast piston on the limit and you give it a bit of a rattle, she's all over.

Speaker 2: 1:10:20

Yeah, the tuning envelope definitely gets a lot narrower and you definitely want to be on top of your game in terms of making sure your fueling's on point and, as you mentioned there, specifically your ignition timing and stay away from knock. And as the cylinder pressure and hence power increases, the chance of you breaking a cast piston with just a very minimal amount of detonation is pretty high compared to the forged piston, as you mentioned. You obviously don't want to be running the engine into knock anyway, but the forged piston just gives you that kind of bit of a safety backstop there. It's probably not going to break immediately.

Speaker 1: 1:10:54

Yeah, it's a safety margin because I mean things can like. You never want to knock anything, but things can happen. You can have people without safeties they can be not running fuel pressure to the ECU, things like that, and you can get a bit of a blocked fuel filter or whatever and it's going to knock when it's lean. If the timing's somewhere on the money, it's probably going to knock. So that's where you can get through that and a forged piston will sort of help you with the safety margin and a 2618 especially.

Speaker 2: 1:11:21

Yeah, yeah, in terms of that piston to cylinder clearance you just mentioned. So how would you manipulate that? Let's say you were building a turbocharged or supercharged street engine versus your drift engine, would you close up that piston to cylinder clearance for the street application? A?

Speaker 1: 1:11:36

bit Probably. And another thing where you close it up a couple of hours, any aluminium block stuff, because the actual bore it grows a lot too. So that's why I mean five and a half sounds like a big number when you're looking at most LS stuff, but you've got to take into account as well of how stiff that that dart block is and how thick the cylinder walls are. It doesn't want to grow a whole lot, it wants to do its best to stay the same size.

Speaker 2: 1:12:01

Yeah, I think the important takeaway from this is you can't sort of take one specification like piston to cylinder wall clearance as gospel on its own. There's all of the other surrounding factors the fuel type, the application, how much load the engine's going to be seeing in a sustained aspect, and then also, as you mentioned there, the block also makes a difference to the material of the block.

Speaker 1: 1:12:23

Yeah, and especially when there's anything that's got a bit of a duty cycle on the as far as holding it flat with a high duty cycle and it's under load, the piston is just going to get hotter and hotter and hotter to an extent isn't it?

Speaker 2: 1:12:35

Yeah, it's interesting what you mention as well about the wall thickness of the wrist pin, because I think that's something that's easy to sort of take for granted that you've bought this aftermarket forged piston. Therefore it's good to go, it's up to the task. But I mean there are upgrade options for all of the aftermarket pistons. I remember back with our drag engine program with our 4G63s. We started with what was already a pretty beefy wrist pin and at one point I was doing a freshen up on the engine. I could barely get the the pin out of the the piston and, sure enough, the thing's bent like a banana and you look at the the pin bosses. I mean, I think this is also down to taking real note when you're disassembling an engine and looking really carefully at every aspect of it, because you know you could see in the pin boss where it had been galling, as you mentioned, and that's another good sign that you're getting flex in there. The other one that I've just come across with our SR20VE turbo endurance engine we just did a freshen up on that and I'm very lucky I did it.

Speaker 2: 1:13:39

When I did Number four piston, I'd actually, I'd heard, on a cold start. I'd heard that it was down a little bit in compression on one cylinder and I think as a tuner that's something I'm always listening for. What does the engine sound like during cranking? And you get a bit of a sensitive ear. You can hear when it's uneven and that's never a good sign. We'd had some issues with valve seats moving around in that engine previously so I put it down to that, but it didn't matter. It was getting a freshen up, so happy days.

Speaker 2: 1:14:08

Anyway, pulled the cylinder head off and here's this crack on the crown of number 4 piston that goes right the way through the piston. Obviously I'm like what is going on here? No, probably a lap away from the whole thing exiting the block. So very, very fortunate there. And the outcome with that, after we got into it, the other three pistons two of them had also cracked and it was just along the edge of the pin boss where it met the underside of the crown. That's where the crack had actually started and then it propagated from there. And, yeah, a bit of sort of investigation talking to a few people about it and it's the, the factory or the, the shelf wrist pin for that particular cp piston is just, uh, not strong enough.

Speaker 1: 1:14:48

You know the, the first experience I had with it. So that hylux that I had on my p plates I've still got that and that's a full race car now. It's competed at world time attack and everything. So it had a back in the day. It had a turbo ls in it and just a budget Turbo LS. It had a SRP forge piston and they've only got a 150 wall pin. And same thing I pull it apart for refreshing up because I'm thinking, oh, you know, start doing the right things, we'll pull it apart, we'll have a look, we'll learn something about it. And same thing I thought, god, these pins are hard to get out. Then you roll them across the bench or on your flat stone or whatever, and they're not straight anymore. Same sort of scenario as you. You pull the pins out and you go, oh, and that thing had been in tune good its whole life. It hadn't copped any pins and stuff, it was just cylinder pressure was bending pins.

Speaker 2: 1:15:32

Yeah, it'll happen. Another one that has caught me out, fortunately. Many, many years ago I learned my lesson. I was rebuilding an engine for one of my customers and on face value it looked like the pistons were in reasonable shape and would do another turn, and it wasn't till sort of I had most of the parts back from machining. I was ready to start looking at assembly and, you know, had a better look at these pistons and went to take the rings off and one of the rings is like jammed in the grooves and you know quickly realized that it's actually been suffering from detonation and it'll close up those ring grooves. So you always want to just I always check now when I'm pulling an engine apart are the rings moving nice and freely on the piston? And if they aren't, that can be another sort of cause for concern.

Speaker 1: 1:16:16

Yeah, definitely. And if you're seeing the same engine back multiple times which a lot of mine I do get the chance to see them again because I'm doing the freshen ups, not only my own personal ones, but ones I do for customers you can measure the like your ring free gap as well. So if you jot that down somewhere, I do an Excel spreadsheet with all my measurements and all my different stuff that I measure, and I'm always adding new stuff I think, oh, you know what. We should start looking at that. So you measure that end gap, the free gap, and then when you pull that same ring out, you can measure the free gap as well and work out if it's relaxed and pulled in similar to what you're talking about but when it's not quite being that bad. Yeah, yeah.

Speaker 2: 1:16:52

Okay, one other aspect with just using factory parts for an LS, and I'm interested so obviously plenty of people putting superchargers or turbos on LSs with stock internals. They're not going crazy with them, and when we're looking at something like the piston to cylinder wall clearance, which we already talked about, that's sort of related to how much heat the piston's going to be exposed to. So we add heat into the combustion chamber, we may need to adjust the piston to cylinder wall clearance. The other thing is ring end gap as well. The more heat that the rings are exposed to, the more they're going to expand and they can get to a situation where they're going to butt together. So for a mild turbo or supercharged build where we're not going crazy and not putting a full rotating assembly into the engine, do we need to address these aspects and loosen things up a little bit, or is there enough sort of margin? I guess in GM's sort of build that it will allow for this without catastrophes?

Speaker 1: 1:17:49

That's a tough one and not everyone's probably going to agree with what I might say here, but I've actually we've put a few brand new engines apart to do different things with, and you think what's GM do? Let's measure up so a common stock LS3 ring gap for the top ring. I've measured five and six down plenty of times which is tight. It's very tight, super tight. And I mean I'm sure that boosted LS as they butt the top ring, I'm sure it happens and it does. But it's surprising that that cylinder must grow a fair bit in the aluminium block, whereas you do seem to get away with it on an aluminium block within reason. So I think that's one thing where the LS and there's plenty of LSs making 1,000 horsepower that have never had the rings out of them and probably another thing that helps that too is most 1,000 horsepower LSs do it for six seconds on the dyno.

Speaker 2: 1:18:41

That was exactly what I was just about to say. I mean it comes down to that sustained wide open throttle abuse just isn't happening. You've got a dyno queen or something that's going to have a quick three to five seconds square of full power. It's not that sustained exposure to temperature that's going to cause the ring problem. I mean to put some perspective around those numbers.

Speaker 2: 1:19:01

For those who are fresh to engine building, a good rule of thumb that I've always sort of worked by is sort of 4,000 of end gap per inch of bore and that generally within reason, is going to set you up pretty well. And if you buy a set of aftermarket pistons they've obviously always come with a guide and specifically there that will be a guide based on is it naturally aspirated? Is it supercharged or turbocharged? Are we adding nitrous? And it's just again trying to get that ring end gap where it needs to be.

Speaker 2: 1:19:28

For the specific application, I do remember years and years ago though I read it was a dyno test looking at what we actually see in terms of differences as the ring end gap changes, and I think people think it's probably actually more critical than it is. You're not going to pick up a massive amount of power, getting that ring gap as tight as it absolutely can be, and the risks of course. If they butt it's not going to end, well yeah, the risk versus reward's not there is it? Yeah? But I mean the flip side is, if you've got a super loose ring end gap, well yeah, maybe you're not giving away a huge amount of power. The blow by into the crankcase is going to increase and then you've got to evacuate that.

Speaker 1: 1:20:09

So I mean I'm not advocating for Not make everything big, but one or two thou here and there. It's not the all and end all.

Speaker 2: 1:20:17

No, I think that's something that's important for those that are fresh to it to understand. Don't beat yourself up too hard. It's not as critical as maybe you think. Speaking of clearances, let's move down to the crankshaft and the bearings. So we've sort of already talked about this a little bit. You've got this cast iron aftermarket block, so you've already mentioned that. Main tunnel rigidity is greatly improved over a stock outless. But but again, is it safe for me to assume you are setting those bearing clearances a little looser than the GM factory manual would suggest?

Speaker 1: 1:20:51

Yeah. So with my Hilux it does sort of 8,500 revs as well. Naturally aspirated deal. Now that does a heap of revs.

Speaker 1: 1:20:59

So that's where I learned that four-inch cranks weren't the go for making power and revving all at once. You can't have everything. I mean a four-inch billet crank in a drag application or something is probably fine, but when you've got just a shelf forged crank they still do the wet noodle thing. And the main spot you see it, and the Silvia does the same thing as the Hilux does. As far as I see similar trends in the bottom end. Number two and four main is where it does the most flexing because just however it goes on, that's where the harmonics, that's where they end up.

Speaker 1: 1:21:31

So you always do something, you always try and give them an extra few tenths if you can, and then like a stock LS can be as tight as one thou on the mains because that grows so much in everything.

Speaker 1: 1:21:42

And I try and keep most of my naturally aspirated stuff with a factory style block, like I do a lot of off-road buggies and stuff like that for the six litre class where we use a factory LS3 block and then pull a bit of stroke out. I try to keep them under two and then just make sure that to some extent the engine gets warmed up before they go and flog it. So they've got oil heaters and all that sort of thing, whereas when you've got components that aren't up to the task but you still want to do the revs because that's what we want to do we always want to do more than what we can do and you just need to open it up, which, opening up bearing clearance, is probably more negatives than positives. But if you don't open it up, it touches, because then there's nothing you can do about that no, it's not going to last very long if you end up with middle-to-middle contact of the bearing.

Speaker 1: 1:22:26

Yeah, no, and if you're under three on like an iron block deal and you're revving the thing, you're going to see witness marks. So you need to be just above three, not too much above three, but about three. Thou on the mains is sort of about the nominal number.

Speaker 2: 1:22:44

And the downsides you mentioned. As we open up these clearances, there's basically a freer path for the oil to flow out, so we see a drop in the oil pressure, plus there's more oil in the crankcase, so windage losses increase yeah, so there's.

Speaker 1: 1:22:57

There's pluses and minuses to that. If you end up having to run a thick oil, so like a 50 weight oil, whereas naturally aspirated engine, I've usually got a 30 in there, so that thick oil. If you end up having to run a thick oil so like a 50-weight oil, whereas naturally aspirated engine I've usually got a 30 in there, so that thick oil. If you run a 50-weight oil with my smaller clearances, what happens there is that the oil can't fit through, so it spends longer in the journal and gets hotter at the bearing to crank area. So you start getting that oil starts pouring out of there. And then the biggest issue you get is that you've got a between a bearing journal and a bearing the rod to the journal.

Speaker 1: 1:23:29

However you want to think about that, there's a hydrodynamic wedge, so the tighter you can have that clearance, the wider section that rod gets to run on. So you've got to get rid of the clearance because it's going to touch. But as you get rid of the clearance, you need to run a thicker oil which still ends up fairly thin as it gets hot. So you end up with the next drama you see is you stop the crank touching it. Then you get funny wear patterns because your your wedge gets small, so you're trying to distribute extra load because you're running the engine harder onto a smaller surface. So that's where you're at the point once you're having to do that because the extra clearance is a band-aid realistically yeah, definitely, yeah. Point once you're having to do that because the extra clearance is a band-aid realistically yeah, definitely, yeah. So once you're having to do that, you just need better parts. So the actual answer to that is you ring?

Speaker 1: 1:24:13

Bryant or Wingberg and you say, hey guys, I need a crank. And you give them the $8,000 or $10,000, whatever it is now, and you cry about that a bit and then you go all right, let's never wreck it.

Speaker 2: 1:24:22

Yeah, and then that allows you to shrink those clearances back down and fix all of those problems.

Speaker 1: 1:24:28

Yeah, and fix all the problems. So everyone it's a common thing that oh, it's a race engine, it's got looser clearances. Race engines with looser clearances is just a real big band-aid for probably generally a lot of it is not having the budget to build the race engine properly.

Speaker 2: 1:24:42

Yeah, that is not having the budget to build the race engine properly. Yeah, yeah, and you see that when you look at a bespoke race engine where all of the components are aftermarket, built from scratch, the clearances on them can be incredibly tight, and that also allows them to run a very low viscosity oil, and you gain some advantages from that as well in terms of less power lost due to the oil.

Speaker 1: 1:25:04

Yeah, and it's funny because people say, oh, lss will make 1,000 horsepower. I keep using LSs because it's real common and everyone, a lot of people, know a fair bit about them. But they say, oh, an LS will make 1,000 horsepower with a stock bottom end. Well, yeah, it will, but unless it's in a road car that just drag races occasionally, it doesn't last a aluminium block ls in a in a proper drift application where you've got, where the car's a fast car and it's got drip like I, I sort of shut it off at 800 I mean any more than 800 horsepower. You're gonna, every time you pull it apart, you're gonna see all the main caps have walked around and it's gonna have leaking head gaskets. You just can't keep the heads on it for a long time and they get hot and they hit limiter and they got a lot of stuff against them.

Speaker 2: 1:25:45

Yeah, I think it's really good for people listening to have a bit of perspective on all of these things, because it's really easy to, you know, see someone on a forum or you know magazine article on this thing making a thousand twelve hundred horsepower, whatever it might be. But you know, doesn't tell the true story and when you're actually living with one of these things day in and day out and you have to have the budget to keep it alive, it can get really expensive really quickly and you dial it back to, as you say, in that 800 horsepower mark and all of a sudden a lot of those problems go away.

Speaker 1: 1:26:17

Yeah definitely Probably. Horsepower isn't really the right thing, it's torque and cylinder pressure is what hurts it. Cylinder pressure is what hurts it around the maximum torque area and then eventually you get through that and most people aren't revving them above 7,000 revs really. But once you start trying to rev stuff, then that's when you start seeing the crank shaft flex and it starts like a skipping rope and it's doing the outside radius as much as it can. That's where you start seeing that when you rev things.

Speaker 2: 1:26:46

Now, one of the obvious standout features of your car, your drift car, is the roots blower, and I did interview you at World Time Attack last year about this. But I mean, obviously not everyone listening to this podcast is watching all of our videos on YouTube. But also, if you're're not, jump on our youtube channel, subscribe. There's some great content on there. Why the roots blower? I can only imagine you would have been able to make more power easier with one or two properly sized turbo charges yeah.

Speaker 1: 1:27:17

So the roots blower was not actually meant to go on that car. Originally I had another practice car it was for it was just going to go on top of an LS1 and just be cool. Anyway, then things changed. I thought, oh, we'll put that on the Silvia, We'll build something cool. I had a 350Z and in my eyes it wasn't as cool as what the Silvia was. I'd had that Silvia for a long time.

Speaker 1: 1:27:37

When I got out of that Corolla I then bought that Silvia and I was building the most insane sports sedan Australia had ever seen, but forgot to do it. I couldn't afford it, so I just thought, oh, I'll keep that, I'll do something with it one day. So I then started building the Silvia and it sort of got built around that blower and there's no performance advantage. There's almost no advantage. Everything about that blower is a disadvantage as far as making a good car. But it just stands out and looks cool and I don't think anyone in their right mind thinks it's a good idea to go drifting with a roots blower covering half your windscreen either.

Speaker 2: 1:28:10

It's a good point. Actually, your visibility can't be that good.

Speaker 1: 1:28:14

No, it's not great.

Speaker 2: 1:28:15

it's definitely not great, alright well, let's talk about why these roots blowers aren't now the sort of the go-to choice. So obviously, when, when we compress air, no matter how we do it, a byproduct of that is we're going to increase the heat of the air. That's a given. It's physics, we can't get around it. However, depending on how we're compressing that air, some forms of you know, supercharging, turbocharging, etc. Are more efficient. They add less additional heat over and above what physics dictates than others, and the roots blower's not really stacking up too well in that respect. No, especially my roots blower.

Speaker 1: 1:28:54

It's a proper truck one.

Speaker 2: 1:28:56

And then on top of this, I have had very limited experience tuning engines with a roots style blower on it, but generally you also want to introduce fuel before the blower because that actually helps seal the two lobes of the blower and prevent sort of a leakage path and that helps improve the efficiency, and that can be challenging or very difficult to do with fuel injection.

Speaker 1: 1:29:22

So yeah, talk us through what you've done to sort of get around around that problem so we've got 16 injectors because obviously when you're in, if you're in a perfect world, you could argue that if you can inject it all on top it's kind of better because you get more of the. So we don't have an intercooler, so all our intercooling is from the fuel, and the fuel it pulls the temperature out of the air. I'm sure there's a proper terminology for that.

Speaker 2: 1:29:47

Yeah, it goes through a phase change from a liquid to a vapor and as it does that it pulls that heat out of the hot air. So same sort of concept as how water methanol injection works as well.

Speaker 1: 1:30:00

Yeah, yeah, exactly. So we've got the injectors on top, which they probably do. Depending what part of the map, it's all different. So, closer to idle, I let the port injectors do a little bit more just to keep it, because it's just messing around doing whatever as you roll in, it pretty well transitions up to the top injectors. So I have the top injectors doing about 85% to 90% of the work and then I utilize the port injectors to sort out my individual cylinder trims, which we get a.

Speaker 1: 1:30:26

You don't get a perfect idea, but we get a rough idea of what's going on in the cylinder from the EGT. So just try. And if you've got one getting hot, I just got simple one-dimensional tables related to temperature on each cylinder and, as if it's getting hotter, it just adds more percentage of fuel. So it naturally tries to keep itself around that sort of 700 to 750 nominal number. And then, if I've got one, that's always more when I'm up it then I just give that whole table a sprinkle of a bit more fuel and then one of the biggest challenges with all this is obviously transients.

Speaker 2: 1:30:59

Yeah, because you've got quite a big distance between the port injectors, which are mounted in the normal location right by the intake port, but obviously your injectors on the top of the blower. They're physically a long way away from the intake valve.

Speaker 1: 1:31:13

Yeah, and you snap that throttle open and the engine sees the air before the fuel gets there. I try and use as much of the bottom injector as I can for the transient, because at least it's on the scene straight away and then it sort of helps it a bit. It's still hard, it's really hard. It doesn't matter what you do, you end up with a slight lean spike for a second and then it goes fat once all the extra fuel gets there. Afterwards. I've tried to maybe someone's better than me out there, but I've put a lot of effort into trying to make that nice and it's just really hard.

Speaker 1: 1:31:45

And another thing I do, obviously, with your injectors up top depend on where they fire. So it's two electronic throttle bodies up there and there's two injectors on each side of each throttle body, so a total of eight injectors up the top and we try to fire them just as as evenly as possible. So it's in. It's like a semi-sequential or batch fire type deal, so it's always using a bit of everywhere. Otherwise I imagine in my head that some of the air can get through without pulling any fuel with it and then you've got a funny mix. But it seems to be working pretty good and the lambdas are always good and stuff and the individual cylinder trims are Kind of got a bit of an egg beater in there, mixing it all up anyway.

Speaker 1: 1:32:20

Yeah, it mixes it up pretty well. Some people struggle with it and we definitely. It wasn't easy and the main part of what was hard was all that. The steady state stuff you can get good, but the transient stuff is hard and it's been good for a while now I haven't had to touch it. And another thing which is really hard to get wrap your head around is the speed of the transient. So the derivative of the RPM change change. So if you have a fast rpm change versus slow rpm change, it changes the transient feeling so much like more than what you'd normally expect.

Speaker 1: 1:32:53

And depending on what the intake air temp was in the blower before you've made the change because I can be, if I'm idling and you see this on on logs from dyno runs or the part throttle, it'll be intake air temp be 60, 70 degrees that's a common number. Then as I roll my foot in it comes straight down. As the boost comes in it starts making power. It'll come down to nearly ambient Really Every time. Okay, yep, so I bed the new engine in the other day and we're like 60 degrees air temp sitting there idling. Then as I put my foot flat it comes down to about 35. It was on probably 27 degree day here and just flat lines at 35. And it'll just sit there. So all of the time that engine spends getting used properly, like when it's under load, it's pretty well within 10 or 15 degrees of ambient as far as the intake air temperature.

Speaker 2: 1:33:40

Impressive with no actual intercooler. No actual intercooling. Yeah, and the term that I was scrambling to find before when we were talking about the effect of the fuel cooling is latent heat vaporisation. So that defines how the fuel will actually pull heat as it goes through that phase change.

Speaker 1: 1:33:59

Yeah, so then it's on E85, which then methanol would be better again obviously. It's probably common knowledge. So the alcohol in that fuel, it just does a pretty good job of pulling all the temperature out of that air. Then another thing I do to try help that intercooling effect is run it pretty well. I don't run it like not overly rich, but on the fatter side. I'll keep giving it fuel until it really wants to fall over as far as power goes. I don't give it fuel until it really wants to fall over as far as power goes. So I don't give it fuel until it loses power. But I'm on as far as you've got your window, you've got your margin that you can run in. You're not chasing that lean edge. No, I'm on the fat side of it and the more fuel you can put in, the more energy of fuel you've got to pull the temperature energy out of the air which helps it. Yeah, that makes a lot of sense.

Speaker 1: 1:34:42

Probably one of the biggest secrets to the reliability and everything of running a roots blower like we do is the fact that it's underdriven. It's underdriven 10%, which isn't a huge underdrive given the engine RPM, but we're only running like seven or eight pounds of boost because it's so inefficient even compared to a good roots blower with Teflon and like a high helix blower and stuff or like, say, a harrot blower or magnuson or whatever, like a screw, screw style blower or turbos, are obviously even better again. So the secret is that the less compressing it's probably not a secret, it's just physics the less compressing you can do with that air, the less temperature you make for starters and the easier it is on everything yeah, yeah and yeah, seven, yeah, 7 to 8 PSI.

Speaker 2: 1:35:24

It's probably. Yeah, it's definitely not doing a lot of heavy lifting there.

Speaker 1: 1:35:27

Nah, it's doing it pretty easy. And then we sort of use the RPM of the engine as well to make a lot of that power. Like 8 PSI on an LS making 800 horsepower probably isn't two common numbers that go with each other. Wouldn't have thought so, no, nah, but it seems to work.

Speaker 2: 1:35:41

All right, let's move on. Mitch, I want to get a bit of insight into what Pull Spec Engines is. So can you give us sort of the 30,000-foot view? Where's it located? How many staff? What's the size of your facility, for a start?

Speaker 1: 1:35:57

So we've got a new shop that we've just set up which is just for the Pull Spec stuff, and we also do some aircraft engines as well which we can maybe touch on. So the pull and spec side of things probably do high class, I guess, or bespoke ls's. So we're not. I've done a lot of just putting cams in ls's and all that sort of stuff, but that's not what we're trying to do now. So we're just doing the nice competition engines, like all dry sump stuff, all good quality components. So you put good stuff in, good stuff comes out, I guess you can say so that's what we're doing. There is just and primarily LSs. Obviously I do a few drift engines being involved with drift stuff. That makes sense. We do some circuit stuff, a lot of off-road buggies as well we seem to be doing lately, so that the sort of high class, nice quality, good race engines is what we're trying to do there.

Speaker 2: 1:36:48

So a couple of points on that. First of all, working primarily just with the sort of, as you mentioned, high class of engine where you've got budget to put the right components in and do a really nice job Sort of a knock on effect from that, I'm guessing you're getting better results out. The end of that and the engines are lasting better Helps your reputation, exactly so not everyone's.

Speaker 1: 1:37:11

We do a lot of stuff, so I don't have to necessarily rely on building engines for an income if that makes sense. So what that is a luxury to me is I can be a little bit picky and only do good engines. And if you do good engine, if you've got a bit of an idea of what you're doing, and you do engines with all good stuff and they're operating within what you've designed it to operate within, they just you build the engine. It goes like an off-road buggy, for instance. You build it to the spec. So I've got like a 600 horsepower flywheel spec for them that we do and they go out and they do their job and they come back and everything you expect is what you see, unless something happens.

Speaker 2: 1:37:50

Oh, and there's always some kind of potential black swan event that you can't foresee when you're assembling them. But hopefully those are the exception, not the norm.

Speaker 1: 1:37:58

Yeah, but definitely your customer base can make who you are as an engine builder or tuner or anything that you're doing. Like it's no different to if you've got a customer that wants to put a good ECU in and they want EGTs and they want coolant pressure and they're happy to put the money into all that stuff and a good loom and all the things that make things good. All of a sudden you look like a better tuner without necessarily being better, Not to say anyone's bad.

Speaker 2: 1:38:21

But the other sort of unintended consequence of this is generally, at least I found you end up making more money from those jobs as well. We kind of went through the, I think, the usual sort of growing pains of building up a tuning business. And you know, to start with obviously you kind of have to take in every job that comes through the door. But uh, you sort of quickly realize that I mean no disrespect. Obviously every enthusiast has a budget and you can only work to the budget that you've got. I totally get it, I was there once as well. But you quickly realize that dealing with the enthusiasts that have sort of champagne dreams and maybe a beer budget at best, it just never really ends well for anyone.

Speaker 1: 1:39:05

It doesn't. And a common thing I see with building engines is, let's say, an engine's $40,000. If you've got the $40,000 engine budget no one thinks about and it's not documented well, sometimes it's like 30 or 40 grand, to put that engine in or the other supporting modifications.

Speaker 1: 1:39:22

Yeah, if you've had a 10 grand engine in there, you can't just put a 40 grand engine in that same hole Like all of a sudden. Now you've got to plumb the dry sump system, which go oh, that's just a few lines and stuff. But if you don't use good quality plumbing and do that right, that wrecks the engine. Then you need a good fuel system. If you don't do that right wrecks the engine. Then you've got the harness and trigger issues and like to do things really nice and reliable. It just costs lots of money and there's no way to change that.

Speaker 2: 1:39:48

Yeah, I think you're dead right there. That is easy to completely overlook, but when you've got a really nice engine it kind of drives the choice that you make for all of the other supporting components, like your fuel system and your dry sump system. So your hand's forced right from the get go and your dry sump system so your hand's forced right from the get go. Another thing that I think's also worth an enthusiast understanding is the cost of maintaining that engine. I mean it isn't a one off cost. You buy an engine I mean your job's not done there. If you're using it in a competition, like it's meant for, it's not going to last forever, no matter what components are in it or who built it. It's going to need maintenance and maybe that's once a season it goes back for a freshen up. So we need to sort of factor that in as well.

Speaker 1: 1:40:31

And that's a really hard one too, because you get, like your average cammed LS in a club race car with a wet sump, and they get in it and they start it, and they don't bother about nothing, and they race it and the thing could last three years, could last longer, who knows. They do last a long time. And then you go all right, this engine's three times as much money, but you've got to bring it back three times as often. It doesn't make sense to them, but it's a hard one to explain. Well, and you don't even necessarily need to bring it back because it's got problems. But if we don't keep on top of stuff when it does have a problem, it's going to be a big Like.

Speaker 1: 1:41:03

Even as simple as every time one of my engines run oil, I always want to see the oil filter, because if you have any little issue like you got your logging, which tells you a lot of stuff, providing they don't delete it trying to get it out, which happens sometimes and then you've got to cut the oil filter every event they go. Oh God, I've got to buy an oil filter every time I drive it. Well, yeah, it's a pretty small expense A small expense exactly. And then priming oil pressure up. Every time you start the engine you've got to take the belt off. You either run your belt to another pulley with a drill or you need to spin the oil pump Like oh God, that's a big job. Then you've got to heat the oil up as well. No-transcript. Just it compounds and compounds the amount of work and to an extent it. For the average club racer it probably takes the fun out of it eventually yeah, I think so.

Speaker 2: 1:42:01

I think that side of kind of educating the customer on what they're signing up for is really important as well. I mean, first of all, it's going to protect your name, because if they're not prepared to do all of that, you probably don't really want to be selling them an engine. It's going to go bad. And I mean also it just sets their expectations right from the get go. Hey, if you want to do this, that's fine, let's go. But here's how you're going to have to deal with this. Are you up for it or not? Do this? That's fine, let's go. But here's how you're going to have to deal with this. Are you up for it or not? Because you're right, you don't sort of turn up to an event, unload it off the trailer, fire it up and head out for a first lap. It's probably an hour's work to kind of get it to a point where it's ready for a start up.

Speaker 1: 1:42:36

It is and it's a proper hour and a lot of things like depending what front splitter and stuff they've got on them, you can't always get to the oil pump and you can't do all them, so then you're having to put the car together at the event and it's a lot for some people, which for me. I've always been so into it that that was just part of it. I'd never thought of it, but as I got more and more customer base, I'm thinking, oh God, this is actually a really big challenge for some of these guys. So I'm getting better at talking to the. Before we go and build this great 600 horsepower at the wheels LS for a circuit car, do you understand what actually needs to happen here?

Speaker 2: 1:43:10

Yeah, case in point there. I mean, it's not specifically my engine, but that's one of the things that kind of started to wear thin a little bit for me with drag racing was with my particular car. The only way we could keep the drivetrain together was to slip the hell out of the clutch, and it had a triple plate clutch in it. You'd get 10 passes out of a clutch, but that was the only way we could make it A go down the strip fast and B not destroy all of the drivetrain. So that's fine. I mean, okay, we'll do a clutch, no worries. But the problem was and this is not my fabricator's fault, it just was was we didn't know what we didn't know when the front end of that car was tube framed. The way it was designed meant that you couldn't pull the gearbox without pulling the engine. Absolute stupidity looking back on it. But it just wasn't something that was factored in and that was a six or an eight hour job.

Speaker 1: 1:44:02

And you're doing this literally every time you run the car and you're like yeah, I don't know if the juice is worth the squeeze on this one anymore. Exactly the same as with some of my customers. Like when you, when you make big power, you need to do the revs to make the power, then part of doing the revs is if you've got a nine inch clutch. In there, the centripetal force makes the things they all go funny. Then you can't use the clutch anymore, so you need a seven and a quarter. Then they want to load their car on the trailer. You're like mate, if you do that any more than three times you're going to need a clutch. Exactly the same thing.

Speaker 1: 1:44:31

Not everyone that's going racing without the team to be doing all the work. It's not that easy to be doing all this stuff, is it Same thing? Is the juice worth the squeeze? You think, oh, oh, this is a lot of effort. But then if someone's willing to put the effort in and you want to win as well, then you, if you don't do it, you just you don't win, do you?

Speaker 2: 1:44:50

no, I mean, I wouldn't change anything about that, but it was just a season of life that's now now been and gone, and you know you look at drag racing specifically as well. It's a. It is a stupid sport because you're spending more and more money on the car in order to spend less and less time in the driver's seat. I do quite like the ratio of driving I now get with circuit racing, but I'm not doing zero to 400 metres in eight seconds anymore either.

Speaker 1: 1:45:19

Yeah, you're not getting that feeling. Drifting is a lot the same. It's a lot of effort and a lot of change in tyres and a lot of change in wheels to do two laps and it's all over.

Speaker 2: 1:45:29

Yeah, no, the tyre budget must be pretty hectic. Coming back to the other point I had on the fact you've clearly just specialised in the LS, it goes without saying there's benefits in terms of focusing on one brand of engine. You just know the engine inside and out. There's no learning curve associated with all of the things that can go wrong because you know them.

Speaker 1: 1:45:50

Yeah, and you've got to do what you're good at too. Like I don't do my primary, what I put the most effort into is naturally aspirated engines too. So obviously we've got the blower on the Silvia, but that's not what we do in a way. So rather than trying to just do everyone's LS everyone that's got a budget to build an LS I try and stick mainly to naturally aspirated lightweight rotating assembly stuff, and I don't like big stroke in LSs because I like to spin them and I like them to be nice. There's lots of things where stroke is probably good, but it's just not the direction that I went ahead and we went ahead with what we do.

Speaker 1: 1:46:30

Yeah, just try and stick with what I know and what I've got my finger on the pulse with too. So I'm on top of I'm always trying to keep on top of like any new developments in rings and getting rid of friction. There's a lot of power to be made there and with gas porting and gas ported rings and all that sort of cool stuff With camshafts obviously camshafts are a lot more important when it's naturally aspirated.

Speaker 2: 1:46:52

Yeah, I think that the whole naturally aspirated engine build. That's really what's going to test an engine builder. It's, and I love turbos, but it is kind of almost a cheat code. You can within reason I mean, you still have to have a combination that makes sense. But if you want more power, chuck another couple of PSIF, boost at it and you're probably going to end up getting more power. But when you're wide open throttle and it's naturally aspirated, there's no more levers left to pull. Everything has to work in harmony in order to get that sort of the synergy and the result that you want.

Speaker 1: 1:47:28

Yeah, yeah, and you've got to. That's like a lot of my engines have individual throttle bodies and stuff on them so you can get into the third wave as well. So you get this extra run up top if you make it, if you've got all your lengths and stuff somewhere on the money and it works where we get into the-.

Speaker 2: 1:47:42

As you're talking, the tuning of the trumpet link, yeah yeah, which it doesn't always within reason.

Speaker 1: 1:47:47

It does what you expect a lot of the time, but it doesn't like shorter doesn't always just go better up top either. There's all sorts of things that happen. But if you can find yourself in the what they call the third wave, you've probably explained it better than me. There's, like you'll see with trumpets, you'll see three torque peaks. If you make it to the third one, a lot of the time you only get to the second one, but it's an extra. It's just a heap of VE that the engine makes because it starts getting happy up there, and that's another way you can make good power NA as well, and if you're not getting there, then you're missing out on 20 or 30 horsepower. That's up there where you can't see.

Speaker 2: 1:48:20

So just more RPM fixes everything. That's what I'm picking up here. Okay, all right, mitch, I'm just aware of the time here, so I think we'll move towards wrapping this thing up. I think we could probably go another hour or two at this rate, but I do want to respect your time. So we'll get into our closing stage here, and we've got the same three questions we ask all of our guests. The first of those is what's next in the future for you.

Speaker 1: 1:48:47

So we're going to keep doing. Obviously we'll be doing LSs for a while, the nice ones. We're also doing a lot of experimental aircraft engines. So depending how things go, that could take over A lot of the LS stuff we're still always doing. But it might just we might be 70% aircraft, 30% LSs.

Speaker 2: 1:49:11

Let's dive into that a little bit. You did mention that before and I did have the pleasure, when I was on the Gold Coast a little while back, of actually going for a ride in an extra 330 aerobatic plane with your father and that was pretty impressive and I noticed then we talked about it the fact it had a pull-in spec engine in it. I've kind of my general aviation background is sort of Continental and Lycoming engines which have zero technology applied to them and I always sort of look at them and think why can't these be nice and modern and efficient? But the flip side of that is they just do what it says on the label, they go forever and reliability is probably worth more than power and efficiency in an aircraft because you can't just pull over to the side of the sky. It doesn't really work like that. So I can only assume there's a bit of liability when you start dealing with aircraft engines.

Speaker 1: 1:49:59

Yeah, definitely so we've got aircraft engine dyno as well. So some of them ideas. You get an idea and you think, oh, this is a great idea and it doesn't always do what you expect it's going to do. So, especially in an extra, it's not the easiest thing. If you have an engine failure you're not always going to put it down safely. So all the bits in that engine are tested and we're confident before it's in there and we've got a whole lot of new stuff ready to try as well.

Speaker 1: 1:50:26

Once we get it, once we run it on the engine dyno and get the confidence in it, a lot of what that thing's got to go good. Some of it's obviously a bit of porting and stuff like that, like the normal thing that you see and anyone that hot rods like homings. So that's it, that engine. It's got a like homing in it, a 580 cube like homing angle valve thing. So it's real common because the technology hasn't gone real far. But they just give everything compression which they got. So a standard like homing camshaft has one degree of overlap advertised, not at 50 advertised. So they're they're about nine to one comp standard, that 580 yeah so I'm sure you 8.9.

Speaker 1: 1:51:01

Actually, I'm sure you can appreciate 11 to 1 compression isn't the answer to make that go good. So what we've done, that's got a bit of porting and stuff.

Speaker 2: 1:51:09

Probably also just worth mentioning, for those who've got no clue about aviation engines, that these are a direct drive to the propeller and there's a limit on the realistic RPM range that we can use, which is generally 27, 2800 RPM. So nothing like an automotive engine. So we don't have that benefit of being able to use RPM as a multiplication factor to make horsepower.

Speaker 1: 1:51:33

Exactly. And that makes the fact of if you just give it lots of compression, makes that worse as well, because you're stuck at that maximum torque type area where it wants to be close to detonating, and they do. They blow cylinders fair out the side of the cow. So what we've done in that is one of the biggest differences.

Speaker 1: 1:51:48

It's got a custom piston in it, a forged piston that we got done, and it's got thinner rings and gas porting and all that sort of stuff and it makes a massive difference. It's just getting rid of some friction, so standard. And it's got a little bit more comp, but nothing like what you see. It's got a bit over nine from 8.9, so like half a point more sort of thing. And what makes a big difference on that is getting rid of the friction. Whereas a standard piston has two top rings and they're both the same part number, it doesn't have an oil scraper ring so they don't control oil. That extra uses next to no oil as well, just from having a proper oil scraper ring and a nice hone finish and all the little things, which is no big deal in today's technology, but it's a big deal for airplanes.

Speaker 2: 1:52:28

Yeah.

Speaker 1: 1:52:29

So that and a little bit of slightly different cam and stuff which we've got our own billets getting done now, so we'll be able to get real radical when I say radical, radical from standard but not radical on.

Speaker 2: 1:52:39

More than one degree of overlap.

Speaker 1: 1:52:40

More than one degree of overlap. There'll be something there to machine it into it. And then we're going to put a nice lightweight valve spring on. Them is one of our next differences and standard. They got like a half inch stem on the exhaust valve. So we're going to. It's pretty, this is big, it's very big sodium filled thing. But we're going to pull that back to like 11, 30 second, which in today's technology isn't crazy, but as far as from what they are, it's a big difference. And then we'll go. They got like a 716, I think it is intake. We'll pull that down as well. It might be 38 actually Pull that down to 1130 second and just without going leaps and bounds and getting ahead of ourselves, just putting a little bit of our race engine technology into them and before you know it, you're going to be massively forward.

Speaker 2: 1:53:23

So this emerging market of aviation engines, are you looking more towards this hot rodding, quite a niche aircraft engine which is the Extra 330 or Extras in general, or are you also looking at just broadly, sort of just general overhauls on general aviation engines?

Speaker 1: 1:53:43

Probably. If you look at what I've done, I've never done anything too normal, so definitely going towards the experimental market. So we'll have all our certification for all the helicopter engines and all the certified stuff. That's still. There's a bit of paperwork still going through for that, but primarily focused on the hot rodding I guess you could say, which isn't necessarily hot rodding as such. It's not normal hot rodding as people say it, it's just getting rid of friction. Yeah, yeah, it's one of the biggest enemies in them. You get rid of the friction without having to add cylinder pressure and the horsepower comes for free. It's just efficiency at the end of the day.

Speaker 2: 1:54:17

Yeah, 100%. Again, one of those areas that's, on face value, very easy to overlook just how important the frictional losses are.

Speaker 1: 1:54:24

Yeah, it's easy to think about just trying to make things go better, but let's just get rid of some of the friction and it goes better for free, all right.

Speaker 2: 1:54:30

well, we just went down another huge rabbit hole, so we'll drag it all back. The next of our three questions is is there any advice you'd give to a younger version of yourself to help reach where you are today in your career faster? And as I'm reading this question out, I'm thinking to myself well, you started pretty early, so I'm not too sure what changes you can make, but have at it. What would you tell us?

Speaker 1: 1:54:52

Probably. In my eyes, I probably got it right to an extent. You just got to put effort in and don't be afraid of having to read and learn and before you just go and have a crack at it. It's great to have a crack at things, but try and tool yourself up the best you can by learning as much as you can about things before you have a crack at it, like whether it be motorsport related or whatever it might be financially in life or whatever it could be. Just put the effort in to learn and understand things, because once you learn and understand things then you can do anything.

Speaker 2: 1:55:23

I think what I really like about your story is the fact that everything you're doing here is sort of self-taught. You haven't really kind of gone out for qualifications and you've been learning on the job. But also clearly, from talking to you for the last two hours, it's pretty obvious that you've got a thirst for knowledge and you're very driven to kind of see how things can be done better. But I think that sort of that passion coming through and you know, I think if you can do something you're passionate about the odd story you'll never work a day in your life.

Speaker 1: 1:55:54

Yeah, and I think what I've done too. I've been lucky to be around a lot of good stuff where I've had the opportunity to learn, and then you just got to not take it for granted. When you're around smart people and good stuff, just anything you can soak in and learn and move forwards, and always, just because you're doing something good, it can always be better. So if you're always happy to accept that, hey, I can be better at this, you can be the best and still be better. So, just doing that, and don't take for granted what people you've got around you. If you're lucky enough to have the right people around you that are smart, then any knowledge you can absorb or learn or move forwards with, just learn what you can. Yeah, could not agree more.

Speaker 2: 1:56:33

All right, mitch. Last question for the day If people want to follow you see what you're up to, et cetera how are they best to do so?

Speaker 1: 1:56:39

Yeah, so probably my two best avenues all my racing, racing, running amok, having fun stuff is on my instagram, which is at mitchell pullen. Then also, any of the pull and spec stuff is as an instagram, which is just pull and spec engines, as well as a facebook page, and we've got a website as well, which is pullinspeccom, which is a little bit. We've got to got to get some updates on there, but in the next few months we'll have that. Yeah, we'll have that tied up. It's just it's hard to keep on top of everything, isn't it?

Speaker 2: 1:57:05

yeah, no, it really is. I'll chuck in there as well. Uh, if you want to see, uh, some pretty cool aerobatics, and see the extra 330 that we've been talking about, uh, instagram hp aerobatics yeah, that's it.

Speaker 1: 1:57:18

That's the old man's instagram with all all the stuff he's got going on there, yeah, and then we've actually got we're gonna this year. We've got a few things lined up to do some stuff with the car and the plane together at some big events. So keep on them instagrams. You'll see some of that pop up and learn more about it all right well, thank you very much for your time.

Speaker 2: 1:57:35

Much great to uh get a little bit more insight into your engine business as well as your drift car, and, uh, yeah, we wish you all the best for the future. We'll keep an eye on it to see what comes out the other end. Awesome thanks, mate. Glad to be a part of the show. If you enjoyed this episode of Tuned In with Mitch Pullen, we'd love it if you could drop a review on your chosen podcasting platform. These reviews really help us to grow our audience, so that, in turn, helps us to continue to get more high quality guests To say thanks. Each week, we'll be picking a random reviewer and sending them out an HPA t-shirt free of charge, anywhere in the world. This is also a great place to ask any questions you might have too, and I'll do my best to answer them if your review gets picked. So this week, a big shout out to VTechJustin from the United States, who has said Like cars, like technical details, this one's for you Simply a great platform, great hosts, guests and professional execution. This is not the horse around podcast, it's knowledge and serious business podcast, great details, content and knowledge galore. Well, justin, thanks for your kind words there and if you get in touch with your t-shirt size and shipping details, we'll get a fresh tee shipped straight out to you. Alright, that concludes our interview and before we sign off, I just wanted to mention for anyone who's been perhaps hiding under a rock and hasn't heard of High Performance Academy before we are an online training school and we specialise in teaching a range of performance automotive topics, everything from engine tuning and engine building through to wiring, car suspension and wheel alignment, data analysis and race driver education. Now remember, you've got that coupon code. You can use PODCAST75 at the checkout to get $75 off the purchase of your first course. You'll find our full course list at hpacademycom.

Speaker 2: 1:59:21

Forward slash courses. Important to mention that when you purchase a course from us, that course is yours for life as well. It never expires. You can rewatch the course as many times as you like, whenever you like. The purchase of a course will also give you three months of access to our gold membership. That gives you access to our private members only forum, which is the perfect place to get answers to your specific questions. You'll also get access to our regular weekly members webinars, which is where we touch on a particular topic in the performance automotive realm. We dive into that topic for about an hour. If you can watch live, you can ask questions and get answers in real time. If the time zones don't work for you, that's fine too. You're going to get access as a gold member to our previous webinar archive. We've got close to 300 hours of existing content in that archive. It is an absolute goldmine. So remember that coupon code PODCAST75. Check out our course list at hpacademycom. Forward slash courses.