Tuned In

Field Report: One Modification TRANSFORMED This Car.

March 20, 2024 High Performance Academy
Tuned In
Field Report: One Modification TRANSFORMED This Car.
Show Notes Transcript Chapter Markers

The 2.9L RB26 swap in place of the stock Nissan SR20 is easy to zero in on here, but it's not the modification that has made the most difference outright to lap times and driver confidence...

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With the ability to get 1500hp from this setup, owner and driver Chris Kostakis shows a lot of restraint and the realities of power vs performance when circuit racing a vehicle that is continually developing along with its owner with help from the likes of Advance Motor Mechanics and 909 Motorsport.

What are the downsides of swapping a SR20 for an RB26?
What are some advantages drive by wire (DBW) throttle control gives?
What are some key considerations of traction control for motorsport?
Does motorsport ABS really make a difference?

These questions and more are covered by Andre and Chris while they were at the Australian GTR Festival at Sydney Dragway and we look forward to seeing where Chris and his engine swapped 180SX head in the future when it comes to an aero package and time attack, although he sure has more than enough to keep a grin on his face as this car sits now!

BUILD OVERVIEW:
Factory SR20 removed
1500hp capable setup, running 900 for drag racing and 550-600 for circuit racing for now
N1 RB26 Block
Carrilo Rods
CP Pistons
Spool Imports RB29 Stroker Kit
BorgWarner EFR 9280 turbocharger
Rams Head Service cylinder head package
Peterson Fluid Systems dry sump system
Holinger RD6 sequential gearbox
MoTeC M150 ECU
Increased tyre/wheel sizing (295 fronts)
AP Racing Pro 5000 R's front calipers
Endless 4 pot rears
Bosch Motorsport ABS system
DNA Autosport Blistein suspension package
Benchmark Solutions torque and traction management strategies
Street registered 🤯

Speaker 1:

We're here at Sydney Dragway for the GTR Festival and while it's not a GTR behind me, it is at least powered by a Nissan RB. We're here with Chris, the owner of this Immaculate 180SX, to talk a little bit more about what makes it tick. Welcome to High Performance Academy's tuned in field report podcast series. In these special midweek episodes, we look back through our archives to find the best conversations we've had through years worth of attending the best automotive events across the globe. We've pulled the audio from these tech filled interviews with some of the industry's most well known figures and presented it in podcast format for you to enjoy as a quick hit of insider knowledge. So, chris, for a start, obviously the 180SX doesn't, in stock form, come out with an RB26 or any RB variant. What was the impetus behind swapping out the SR for an RB?

Speaker 2:

I wanted big power, reliable power, so we could just run all down the track.

Speaker 1:

Obviously, more capacity and more cylinders is a reasonably easy way to go about doing that. However, the car is being used for circuit racing as well. Is there a downside in terms of the weight balance? The RB physically is a large, long engine and it's a cast iron block, so it's also heavier than an SR. Yeah, what's your take on that?

Speaker 2:

There's definitely a disadvantage having the RB engine. It's definitely heavier. We can feel the weight in it. Trying to trick that by putting 295 rubber on the front, built since it's been suspension all around by our DNA. So it's definitely helped me go around.

Speaker 1:

Let's dive into the build itself. So, starting with that engine, obviously in the RB world there's hundreds of different engine combinations. What specifically have you gone with?

Speaker 2:

Some mechanics have decided that put a. It's an RB26 but it's a 2.9 stroker kit. We had a Ram's head all the way through, all the way out. It's a 90 280 EFR turbo and behind that we've got a Hollinger Sequential the RD6, with a MoTeC M150 and it's completely dry.

Speaker 1:

Summed, let's dive back into each of those elements. So first of all, in terms of that 2.9 stroker kit so you said that's still in an RB26 block. So there's obviously the N1 in the standard block. Which way did you go there? The N1 there Is that just because it's getting harder to find a good condition standard block and starting with a brand new N1 block means you've got something that's in no quantity.

Speaker 2:

We had a previous block and we had it all tested and it didn't meet up. So my mechanic said let's just start fresh, let's just go the best and don't have any more headaches.

Speaker 1:

And the rotating assembly there. What's the components that go into that?

Speaker 2:

We've got the Correlo rods, the CP Pestons, it's got the spool kit which takes you to the 2.9.

Speaker 1:

Now again, just coming back to the capacity. There's a variety of ways of going about this, and obviously one of the common options is starting with the RB30 block, which, in its home environment, is definitely not a performance engine as such, but it's been well and truly proven to be capable. Once you made it to an RB26 head Taller in the block as well, you always didn't go that route. Is there a reason why?

Speaker 2:

My mechanics ran this combination in one of their cars before and they did an 8.2 down the drag strip, so it makes plenty of power. It's very reliable. She's built for 1500 horsepower, but we're only running 900 horsepower at the wheels Only. As in yes, done it okay. Yeah.

Speaker 1:

I don't even know how you cope.

Speaker 2:

Oh, no, no, it's hard. It's hard, but actually on the track we try and drop it down to around 550-600.

Speaker 1:

Okay, I mean getting the power to the ground is obviously really the key here. It doesn't matter if you're making 900 or 1500 horsepower first going up in smoke. So you mentioned sort of 550-odd horsepower there. Are you using any tricks around boost per gear or boost versus speed to sort of try and match the torque output of the engine to what the track will handle?

Speaker 2:

Yes, we've had a bit of traction issues. But Ben from Benchmark Solutions has reprogrammed the ECU with the gear shifting and also we're trying to not use traction control at all, just with torque management. So we have a boost per gear and we've had to take a little bit of power out of it and a bit of torque out of the mid range.

Speaker 1:

Alright, is there a reason why you don't want to run traction control? I mean, this becomes a bit of a controversial topic. Actually, there's a lot of mixed opinions on traction control, for and against. Yeah, I'm interested on your take on that.

Speaker 2:

Okay, this is an interesting point because We've got to try and use traction control pretty much as a safety. We feel like it does take a bit of power out way too much. But the way it's been tuned now we've got three different traction control settings so we've upped it to about 12.5% slip and we feel like at this stage for the track, the way conditions are at the moment, with the tyres that are running and the weight of the car, just that little bit of slip going through the corners actually really benefits me.

Speaker 1:

Yeah, again, there's obviously different takes on this. I think what you've mentioned there sort of matches my own take on traction control. A lot of people will give the engine as much power as it can make and then rely on the traction control to pull it back. But it is a reactive system as opposed to proactive, which means it has to start wheel slipping or wheel spinning before the ECU can come and intervene, and there's always going to be some level of latency in that. So I think if you can do a really good job of matching the torque output of the engine to what the track can handle and just let that traction control be there in the background, just in case, I think that's quite smart and, as you mentioned there, allowing some slip as well, quite important because it allows you to actually drive the car using the throttle. Is that your sort of findings on that?

Speaker 2:

100%. I agree that yep perfectly.

Speaker 1:

Let's come back to the engine combination you mentioned. It's dry something there and obviously pretty common in an all out circuit application. Can you talk us through the components that went into that?

Speaker 2:

Yeah sure, we actually have one inch oil lines going underneath the car from front to back, supplying the dry sump setup that's in the back. The mechanics are saying look, there's so many different oil systems you can have, but with RBs they're known to have problems. You've really got to feed up, just get the best oil system you can. So we went full dry sump.

Speaker 1:

Definitely, the factory oiling system in the RB is known to be problematic and the oil pump itself is a potential failure point. One of the other elements with the RB26 is the oil flow to and from the head. That really needs to be addressed as well. In stock form they do tend to pump a lot of oil up into the cylinder head and it can't return that easily. But of course in the aftermarket there's solutions for both of those elements. Are you interested in expanding your automotive knowledge? Start your free lessons with us today at hpacademycom. Forward slash free. Let's move back a little bit. You said you're running a Hollinger sequential gearbox, so there's a range of those from Hollinger. Which specific model are you running?

Speaker 2:

It's the RD6 gearbox and we've got the proper Hollinger sequential knob.

Speaker 1:

Okay, so talk us through that sequential knob and how that works clutchless shifting.

Speaker 2:

Yeah, so it's just clutch for take off and the way Ben's tuned it it's clutch us all the way through, from all the way up to the six and back and auto bleeps, rev matches and it's surprisingly very dry all down low on the street. So anything under 3000 RPM it just falls into gear without it like water.

Speaker 1:

The clutchless upshifting is pretty common, but a lot of people will still retain you in the clutch manually for the downshift. But advantages there with the auto blip, yes, some will argue it takes a little bit of driver skill out of the equation. I'm not here to argue that. But giving the ECU control of the blip on the downshift, does that add to the gearbox reliability and, just as importantly, your ability to optimise and maximise the braking performance?

Speaker 2:

Just for the longevity of this gearbox, I wanted to try and get it as best as possible. So, with the computer matching at the right revs and allowing it to accept through the dogs, I think it's the best way.

Speaker 1:

Of course, this does require a conversion to drive by wire throttle, something that the 180SX obviously never came out with. So that's an element, that's a requirement.

Speaker 2:

That's right. Yeah, now the drive by wires help me a lot, even just even on take off, and it really controls the whole car.

Speaker 1:

Another element which you can do with a drive by wire, which is much more difficult to do with a conventional cable throttle, is map the relationship between the driver's pedal position to the actual throttle position at the engine. Is that something you're taking advantage?

Speaker 2:

of Definitely just being so overpowered and hard not to keep the accelerator down all the time. We've got an extra three buttons on the keypad where we can have 65% throttle opening. So if I'm full throttle it'll still only give me 65%. If I think I need more, we can hit another button and it takes us to 85% and then if we think we can just keep going, we've got maximum traction and we're feeling good and we're in control, put it to 100%. So not only boost per gear, but throttle position opening. It really helps you drive this car.

Speaker 1:

And that all comes back to the torque management that we were talking about earlier. Correct, that's right, exactly right. Alright, we mentioned the braking performance, particularly where you can maximise that and concentrate on your brake effort as opposed to heel and toe downshifting because the auto blips doing that for you. But this sort of drives into the larger braking package, and this also is running Bosch Motorsport ABS. So can you talk to us about, first of all, what the physical braking package in terms of Rotors calipers is?

Speaker 2:

Yes, we've got the AP 5000Rs at the front end and we've got four part at the back. This braking system that has just been installed with the Bosch Motorsport ABS has totally transformed the car, the driving. I feel like it's pretty much buying insurance, where I hopefully don't put it in the wall so it'll just pull me up and keep me on the black stuff. But it has taken just over four seconds a lap off my time, which is absolutely nuts, having this much power and trying not to brake or flat spot on a tyre because I had no ABS before. So it's very hard to try and get your head around, smashing the brake pedal as fast as you can, as hard as you can, on every corner. So there's no modulation at all, it's exactly as hard as you possibly can and then you can trial brake off through the corner.

Speaker 1:

So you're really treating the brake pedal like a switch in essence.

Speaker 2:

Exactly, that's a good way of putting it. It doesn't sound good, but it feels like I'm cheating.

Speaker 1:

Now, 4 seconds is an absolute eternity to drop off a lap time from one modification and I'm guessing there's a little bit more to it than that. But you know like that most people will try and chase with power but braking is actually a more viable way of getting that lap time down.

Speaker 2:

Ah, exactly right. Like back in the days, always think about is just how fast we can possibly go, and we never thought about brakes because we want to go faster. But this has actually made the car safer, give me a lot more confidence, and it's definitely taking a lot of time off.

Speaker 1:

Now, quite often in a full on race car build. The factory master cylinder and brake booster will be deleted and a pedal box will be installed instead. I have noticed that you are retaining the factory brake booster and master cylinder. Why didn't you go the route of a pedal?

Speaker 2:

box. The main reason is it's a street registered car and it's just easy to drive.

Speaker 1:

Are we likely to see this competing at world time attacker at any point, and where would you sort of see the lap times coming in in terms of where would you sort of be in the class?

Speaker 2:

At this stage I'm going to probably have to wait for the following year. I have no error on the car, but we're down to a 138 with no error. We're going to try and take a couple seconds off that first understand the mechanical grip of the car and then slowly put some error on the car.

Speaker 1:

I mean, I think the thing to keep in mind here, with lap times around Eastern Creek as well, is when we're comparing to world time attack, where aero over the last five or six years has become so prevalent. That is an absolute game change in terms of lap time. So you're really going to be held back at the moment with the lack of aero.

Speaker 2:

Most definitely, most definitely. I see people just bolting aero on and taking huge chunks off, and also it's actually a safe way of driving as well. But I do enjoy that mechanical feel and learning to drive the car, so I'll definitely get there one day.

Speaker 1:

The car's an absolute credit to you. It is immaculate in every way, shape and form. If you've got any other plans for it in terms of further modifications, is it going to see this aero for world time attack in a couple of years and what else is on the agenda?

Speaker 2:

I definitely think I will. I'll be short, changing the car if I don't it's got. It has everything for it to do. Well, I know it does have big, heavy engine in the front, but I just like that power, the sound and the reliability of it.

Speaker 1:

I can't argue with that. Look, thanks for the chat there, chris, and hopefully we can catch up again on camera for that world time attack in the future.

Speaker 2:

That'll be good. I would love to thank you.

Speaker 1:

If you enjoyed this podcast, please feel free to leave a review on whatever platform you've chosen to listen to it on. It goes a long way to help us getting the word out there. All these conversations, and much more, are also available in full on our High Performance Academy YouTube channel, so make sure you subscribe. It's a one stop shop when it comes to going faster, stopping quicker and cornering better.

RB-Powered 180SX Track Build
Car Modifications and World Time Attack