Wanted to set up my car for autocross me that I have a second daily driver. Been using 215/45/17 front and 235/45/17 rear. I like the look of wider tires such as 255 in rear with coilovers. But really what sizes are optimal? Assuming I am buying performance tires designed for it.

for autocross you want a low profile. The smaller radius gives you the edge. Notice how many tall tires there are on the course? Right.

You also want sticky compound.

That's the best I can offer.

Arn

quote Originally posted by Arns85GT: for autocross you want a low profile. The smaller radius gives you the edge. Notice how many tall tires there are on the course? Right. You also want sticky compound. That's the best I can offer. Arn

Low profile, as in i am fine with 215 and 255, but I should look into getting 215/35/18 and 255/35/18? or 35/17?

Compound is more important than size. For size I lie to use something common, so hopefully you can score some from a road race team.

225/50-15 is great, if your brakes still fit inside a 15" rim.

225/45-17 from GrandAm competition cars
235/40-17 is great

The larger rims usually weigh more, and this hurts acceleration a bit.

Daveg

quote Originally posted by daveg: Compound is more important than size. For size I lie to use something common, so hopefully you can score some from a road race team. 225/50-15 is great, if your brakes still fit inside a 15" rim. 225/45-17 from GrandAm competition cars 235/40-17 is great The larger rims usually weigh more, and this hurts acceleration a bit. Daveg

With my research, i've found that the tires actually weight more than the wheels. the 17" wheels I found are about 16.5lb where the 215/45 tires are about 22.5lb

which theoretically should be somewhere around 40lb

[This message has been edited by Shill (edited 07-15-2013).]