No competent driver likes a car that moves around under braking and is lazy to turn in or out of a corner for no good reason, so they throw many OEM suspension components in the rubbish bin, including factory rubber bushings. Why?
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James Bourn of Powerflex explains that while rubber bushings, aka bushes, provided by the OEM are good at cutting back noise, vibration and harshness (NVH), they are not made to last, nor are they made to perform. They are made to tick the right boxes for the price without compromising handling so much that they get land vehicles with poor safety ratings, as well as lasting just long enough to not be a warranty claim.
For better performance, one alternative is to remove as much compliance as possible using solid bushes, mounts and spherical bearings etc., such as you find in many dedicated motorsport applications. But this, 100% without fail, introduces incredible NVH that is white noise on a race track and permanent hearing loss inflicting, or divorce, territory on the road.
Instead of solid mounts or rubber, we can have our cake and eat it too with polyurethane options instead which offer less compliance than OEM rubber bushes along with a longer lifespan, to the point they come with a lifetime warranty (but only for road and classic car use, NOT the BLACK SERIES aimed at motorsport sadly!), along with levels of NVH that won't give you PTSD from a 12-hour cross country road trip.
On top of that, polyurethane bushes will give you, the driver, more confidence in the vehicle leading to more consistent lap times and pace, making better use of all that time and money it takes to get your car out on track in the first place.