TMyers

I now have 4 autocrosses under my belt. Car is a 08 C6 with F55 suspension. The first to events where run with stock runflats and the last 2 with Kuhmo XS. Huge difference. I am doing well leading by division, novice so I don't really have any complaints. In fact last race I ran the fastest time in all the stock classes.

But I am really trying to find that perfect airpressure and really don't know how to go about it. First run tire are always cold and will both under and over steer. Though after one run they stick very well. I am running 36 psi front and 32 rear. I am not rolling over the tires at this pressure but it is close.

Other information alignment is -1.0, -.5 front/rear camber and 0 toe.

naschmitz

Hopefully your tires have a range of pressures where they work well and not just one specific pressure.

Runflats had the narrowest range of usable pressures I have ever seen with steep dropoffs in performance just outside those limits.

Best way is for you to figure this out for yourself. If you can, go to an autocross test & tune event where you can get several runs, and do the course over and over while making 2psi adjustments so you can feel how the car works over various combinations of pressures.