Tires/Rims Rotate with Racing Tires?

[WardL]

I bought a spare set of used wheels racing tires. Was going to get the standard 335/35 17" for the (17"x10.5") rear and 275/40 17" for the (17"x9.5") front. Then I read a suggestion to rotate tires front to back, side to side between races. Hmm, now I'm wondering if maybe I should go with four 275/40 all around. I bet the 17"x10.5" rims will scrape when they are on the front. Who knows if the 10.5" wheels will scrape when on the front?

Anyone want to trade two 17"x9.5" rims for two 17"x10.5" rims? They are Halibrand pin drive knock-offs for SPF. Looks like brand new 17x9.5 are $440 each

[bobcowan]

One year I tried running all four tires the same. That didn't work as well as I wanted it to. My car does a lot better and has better balance if I use a staggered set. I swap the tires side to side every day.

[SwiftDB4]

Ward,
Forget about using 4 identical wheel/tires for rotation. On both my GT40 and Lotus Europa that I do track days with rears are wider than fronts for better cornering balance. Unless you do an insane amount of track days your race tires will probably get old before you wear them thru. Race tires harden quickly and are pretty useless after 1 or 2 years. As Bob says you can change L & R sides if camber wear is uneven.

[WardL]

OK, thanks. Since I'm very new to this, I didn't know race tires were useless after 1 or 2 years due to hardening. Do they get hard sitting on the sales rack or only due to heat of racing? The autocrossing I do I don't think the tires warm up as much with the cool weather in the NW and the short track. Thanks,

[bobcowan]

Yeah, over time they do get hard. Street tires do the same thing. Check the manufacturing date stamped into the sidewall. They shouldn't be more than 4-5 years old.

They also get hard with repeated heat cycles. You're right - with autocross they don't get that hot, so they do last longer. They only way to know is to check the durometer; but you would have needed to do that when they were new.