I took my '95 to its first real auto-x today...
The car seemed to be consistantly bottoming out the rear tires on the upper fenderwells.
I should emphisize this car is DEAD stock chassis-wise with the exception of Pro-kit springs and Bilstien shocks. Tires are 245/50Z16's on the stock 16" wheels.
It doesn't seem like the car is low enough or has enough tire for this to be a probelm.
Now mind you we were pushing like mad - turning low 53's on (crappy) street tires with nationally competive A-stock Vettes (Mckenna) turning high 49's on Victoracers.
This is a t-top car and I haven't gotten my SFC's yet, is it possable that the chassis is flexing that much? Are the LCA bushings deflecting?

All opinions are appriciated

 

More than likely the rearend is a little off center from being lowered, and one side is hitting. Pull the wheels and look for shiny spots. An adjustable panhard bar can be used to center the rearend.

 

Well, not sure those are revalved Bilsteins or not, but I know when I cornered hard that I'd rub one of my tires on the inside of the wheel-well, usually my right side (pass) tire. Stock panhard, stock rubber bushings, thats is my guess, but look for where your marks are. When this occurs it almost feels like you hit a curb.

You may also just be hitting the jounce spacers? Did you shorten them? Since you lowered it did you put LCA brackets on? I drove mine around without them after lowering the car and the rear is damn near uncontrollable.