I have an 04 GT lowered on H&R super sport springs. I have some 18x9 saleen replicas and was wondering if I could use a 285/35/18 on the front. I know the back would be fine.

 

May be a bit tight, plus not sure I'd want to run a 285 on a 9" wheel in the front. Depending on brand 285 is pushing the limit for a 9" wheel.

 

So I'd be better off with 275/40/18 is what you're saying?

 

I'd run a 265/35 (or 40)/18 on an 18x9 wheel up front. I believe 275/40/18s are about an inch taller than stock, which may rub the inside, but a 275/35/18 is closer to stock ratio . . .

 

285's will rub. And 275's will be tight depending on your wheel backspacing. I had the factory 17's, now have 275/35/18's. Look at some tire circumference calculators online to find the speedometer difference.

 

My buddy just put 275/35/18s on his front 18x9 Saleens. No issues, but I would get the 03-04 Cobra steering stops just in case. I had 275/40/17s on my '00, on 10th Anniversary Cobra wheels, and the stock steering stops rubbed on my inner rim before I switched over to the Cobra steering stops.