michaelkrelina

I think this would work, as other manufacturers recommend a minimum 10.5 rim width for 315 tires. Hoosier, however, recommends 11 inch rims for their 315 tires. Is there a fundamental reason for Hoosiers needing wider rims to function well or is this their way to encourage optimal performance for prestige purposes? Is there likely to be a major performance drop of A6 in autocross on Speedline 18x10.5 as compared to 18x11 rims?
Mike

Z06Fix

Works perfect

Most if not all the SS C5 Z06's are running 315/30/18 Hoosiers on the back.

michaelkrelina

How does the car handle? Does it oversteer with all 4 315?
Does the front fit well enough?
I tried an R888 315 and it seemed to fit but I'm not sure that a major bumb would not cause the tire to hit the fender. On the inside the tire was millimeters away from the breakline.

spazegun2213

handling because of tire size is nearly a moot point. 315's simply allow "equal" mechanical grip on all 4 corners. I run 315's all around and think people are silly for running anything else. You may end up raising the front of the car a little because 315's are WIDE, and stick out a bit. As for the brake line, take a few zip ties and tie it out of the way if you are concerned.

Z06Fix

The car does tend to oversteer with the square setup on it. This can be countered in alignment or better yet a stiffer front bar.

fatbillybob

I got a stock z with t1 bars only and run square but not as wide. My car does not oversteer at all in fact it still understeers. I would love some oversteer. The only way I can get oversteer is to cheat with throttle oversteer to try and get the front to bite.

LouisvilleZ06

I'm thinking of running 315/30/18 all around this year on stock rear speedlines myself. With the shorter profile 30 series will I experience alot of rubbing? I'm planning on using Kuhmo XS street tires.

Ive heard people say its fine and others tell horror stories of rubbing the fender. whats the truth?

My car is lowered all the way on stock bolts, would simply raising the front a bit alleviate any issues?