Austin:

Here we go again - you cannot make absolute statements about an unknown -it is all about the car and getting to a point where the car is neutral on a high speed corner. I race a viper and it won't run with anything less than a 3.35 on the rear. You cannot get the same size tire on the front due to an obstruction when you turn in. The larger the tire on the rear, the earlier I can get on the throttle after the apex. We all cheat and try to get on the throttle before the wheels are straight, the larger tire just gives you an advantage.

When I set the car up the changes were made to get it neutral, then I played with the tires, but, still keeping the car neutral. The vipers are not a neutral handling car when you start, but, after I tuned mine there is no under/over steer unless you make a mistake with the throttle.

If you follow the serious racers on the autocross forum, everyone wants more tire than a 2.45. The jury is out on the exact set-up because we don't have enough seat time with the Kumho's and Hoosiers to define the best tire for the GXP. I can tell you this I will be starting with the 2.75 Hoosiers and if there is oversteer and I can't tune it out, bigger tires will go on the rear.