99mustanggt

Not to hijack the thread but are stock GT wheels 8in or 9 in?

DTK

My stock rims are 8's on my '04

P Zero

Not even close, if the stock tire size is 245/45/17, in order for a 275 to have the same overall diameter as the 245, it would have to be 275/30/17.

To answer the post, 275/40/17's is the widest you should go. Even those buldge off of the rim quite a bit.
-P.

trance565

a little bulge is always good, keeps your wheels safe from curbs if you are a curb hugger.

PushinTheLimit

Some guys will put their 315 Nitto's on a 17x9 rim and not have any problems. But Nitto's tend to be not as wide as per say Goodyear or BFG, etc. If you go with those other two i mentioned, 275 will work just fine for that.

bigedog8

u dont need an insanely wide tire to hook with good rubber... I have 255 MT DR's on 16" wheelsand lemme tell u that u dont need anything wider until u make some serious power. before the supercharger all my car would do was bog like crazy off the line because they hooked so well. and that was launching from 4500+. anything in the 245-275 range with a good drag radial will give u all the traction ull need.

DTK

P Zero, you are not even close!

Go plug in the tire size here:
http://www.1010tires.com/TireSizeCal...&reset=yes

Your quote of 275/30 is off by a mile...over 8% to be exact

As I said before the 275/40 is the closest to stock diameter at .08% off.

P Zero

That calculator is theoretical. If you dont know how tire sizes work let me explain them to you. The first number in the series is the width of the tire in mm. The second number is a percentageof the first. THe third number obviously is the rim diameter.
In theory if all tire manufacturers follwed this then all tires would be the same size, got news for ya, theyre not. Each tire manufacturer measures their tires from a different spot on the tire. For example, if you were to compare a BFG KDW to a Michelin pilot, the first thing youd notice is the BFG is wider than the michelin by a considerable margin. Michelin measures the width of their tire from the sidewall, where as BFG measures actual tread width (even though Michelin owns BFG).
So DTK in theory you are correct in actuality you are not. I guarantee that with the 275's youll have a taller tire (even though its supposed to be less than 1%). In actuality Id be alot closer than 8%.
Another example, I run 225/40/16's, if that calculator was right they should be just as wide as a 225/50 or 60 even, just witha shorter sidewall. But its incorrect, my 225/40's are over an 1" wider than a 225/50 and over 1.5" wider than a 225/60. And theyre definitly NOT 40% on the width.
-P.

jmac72187

It is a calculator. That means it is a tool to give you correct answers. If it gave you wrong answers, it would defeat the purpose of the calculator.

1hotdrp

wouldnt go anywider then275