Neil B

Hey guys, I'm looking to take some gear ratio out of my C5 for the Texas Mile by using a larger rear tire diameter. What is the largest diameter (Y) rated non-drag radial that will fit a C5 without rubbing the inner fender? It can be a 17, 18, or 19 inch wheel. My car is flared so width isn't a big issue.

0Luke@tirerack

27.0" - 27.5" is the tallest diameter I have seen on a C5 without issue

Neil B

Thanks Luke. I'm currently running a 345-35-18 Hoosier R6 which is 26.8" tall. I was hoping to drop RPMs through the traps by a few hundred RPM using a 28" tall tire. But it's difficult to find a 28" tall tire with a (Y) speed rating.

Allthrottleandsomebottle

Not sure of your budget, these work fine if you can find them...
Jag XJ220 rears:345/35ZR18 Bridgestone Expedia S-01 street tires

Neil B

Thanks I already have 345-35-18's. Trying to go bigger to take some gearing out of the car. I ended up with a 325/710-19 road race tire which is 27.9 inches tall. It's tight and might kiss the inner fender on big bumps, but should work.