I would say 8" for fronts and 9" for rears. I read on here a while ago that for tire sizes, you go 1 inch larger than the rim. 1 inch = 25 mm, so 8*25=200+25=225, so that's how I got the front. I'm not so sure how accurate this is since the stock wheels don't go by that. I also have a friend w/ a 94 Vette and they have 285's on 9" rims stock, so who knows.