preston_brown

Hello everyone,

If you looked at my race car thread, you see the car is finally back on track. Very happy indeed about that! I have 18" BBS rims, 9" wide front and 11.5" wide rear. Back when I got the car I picked up a set of 245/40R-18 for the front, and 275/35R-18 for the rear. The front is a good fit but the rear really is too small for the rim. It works, but barely.

The good thing is the circumference of this pairing works well.

Suggestions on a different tire size / combination that I can get in DOT R rated compounds?

Earlydays

With Hoosier R7's you can go 295/30, also matches the overall diameter you're looking for.....

preston_brown

That sounds like it might work. What's really the optimal width for an 11.5" wide rim?

Bill Verburg

295/30 x18 are generally spec'd 10-11" wheel
305/35 x18 10.5-11.5"
315/30 x18 11-12"
though there are a few outliers that go .5" up or down from those #s

generally the best performance from a tire will be obtained when it is mounted on the widest wheel w/i spec, so for an 11.5" wheel 305/30 x18 but the pickings are slim for that size so I'd be looking at 315/30 x18 @~25.5" tall

maybe a 265/35 x18 @~25.3" in front these generally want a 9-10.5" wheel

you'l have to balance available sizes in the brands you want against front vs rear sizes and best size for the wheels