I agree with you on that! When I first went out on them I thought they were terrible. It took 3 laps (10 minutes) of hard driving to warm them up. They were great after that. Definitely not an autocross tire.G Stamatakos said:The Michelin Sport Cup work great when run for more then 4-5 minutes, i run in Solo 1 and i could not get any heat in them on a semi cool day 60-70's, 1 warm up lap and three hot laps are not enough for these tires, open lapping they are great or on hot days 80's+.
Got a few questions:Running the smaller 275/40x17 on the front for the track and larger width rears will give the car poor turn in and static understeer in mid corner. This holds true for both track and AutoX, high or low speed. The only time the 275/40x17 is desirable is in the rain with rain tires on.
There are a number of solutions:
1. the T1 alternate to stock set up is fine. 10x17 wheels in the front and 11x17 in the rear with 315/35x17's all the way around. These are SCCA legal. for T1
2. If your not bound by SCCA T1 rules you can do even better.
My personal preference is to run Hoosier 305/30x18 on 11x18" wheels in the front. I like the 315/35x17 on either 11 or 11.5x17" for the rear. The reason I like this combination is:
- the tire contact patch is almost equal F to R.
- this reduces the static and mid corner understeer and makes the car as neutral as possible.
- the 30 aspect ratio on 18" in the front reduce the side wall flex and allow crisp turn in with hardly any flex
- this also reduces dive under heavy braking
- the larger contact patch in the front besides reducing understeer and flex also increases front grip and allows higher cornering speeds
- the 35 aspect in the rear allows more side wall flex in the rear than the front and allows better F>R weight transfer under hard acceleration this allows quicker straight line trap speeds and higher corner exit speeds
- there is also more grip and tire contact patch in the rear which aids traction.
3.I have been toying with the idea of going to 335's in the rear but you either need to be tubbed or with more positive offset which allows them to stick out. also I fear that a 305/335 commbination would regress the car to the understeer condition.
4. the 315/335 F/R combination might be an alternative though.
The is no need to reprogram and the nice thing is all of these tire combinations have 25.5" diameters