Quote:
Originally Posted by glamcem
I would expect them to be different (stiffer) not the same in a lower package to compensate the load with the added stress on those springs 
What I meant to say is; 1LE is a track focused car with a superior suspension tuning and it works with that specific formula (suspension geometry, MRC tuning, bushing stiffness, anti roll sway bars, ptm, e-diff, tire compound ..etc ) , the whole reason I am considering getting one is because it's a well-thought package and I don't necessarily have to change anything with the possibility of hurting that otherwise I would simply build another track car (like a C5 Z06 or C6 GS ) with coilovers, rollbars, roll center kits and whole shebang.. I am even skeptical of going with a very aggressive compound for the track days since MRC is tuned for a street car (unlike the Z07 packages that come with Michelin Cup 2 tires) so anything more aggressive than the new Goodyear Gen 3 tires, Bridgestone RE71Rs and/or Nitto NT01 should affect the whole tuning, in fact I have a friend who did that and ended up changing to coilovers to gain back the benefits
Don't get me wrong I am not trying to judge anyone's decision but I find it a bit counterproductive; getting a track ready car and paying the $6500 premium and the ditching that and going with lowering kits and/or coilovers each his own of course
It looks like the more the suspension system gets sophisticated, harder to anticipate the effetcs of each change/mod |
+1, these cars are very finely tuned to their package and tires. You can't substantially change the tires' traction and get all the benefits. This is especially true for MRC cars where GM uses softer springs than required, and makes up for it with stiffer shock dynamics via MRC. This trick allows GM to keep very high comfort levels at the steet, yet provide enough support at the track, but it also means that the springs are already challenged for the duty, and increasing traction throws the fine tuning off. You can't just switch to stiffer springs, either, since that would make the shock valving off-target. FYI, Z07 springs are at 190 N/mm up front, while regular Z06 springs (which also have MRC) are merely at 117 N/mm; that's a huge difference, which is caused by more track focused tuning, but most importantly, more traction from Cup 2 tires (that I don't even like).
In short, when you increase the traction in MRC cars or modify the suspension (like springs), for max performance, you either have to buy an aftermarket MRC controller (like what DSC mototsports has) and hope that you're still within the tune range of the shocks, or switch completely to coilovers.