looking for some competition tires and found this size on tire track. Gonna bee used for circuit racing with 245/40/18 up front.

 

Thats too wide for an 8.5" wheel, the widest you should go is 255

 

The correct size tire is 275/40-18”, but as redlude97 point out, a 275mm tire is too wide for an 8.5” wheel.

--Spike

 

what u r saying guys is true, but I was thinking of having more beef at the back to cop with my supercharger.

Not too many options with R compound tires

 

^^ I understand why you want/need a tire with this width, but it's too wide for the wheels you have; and its aspect ration is wrong. You need new wheels.

--Spike

 

Hoosier 275/35R18s work fine on the rear 8.5-inch track wheels AND the front 8-inch track wheels. Even your local tire company can mount them.

I run 285/30R18 Kumho V710s on all four corners (8-inch and 8.5-inch) on my '05 Track. Yes, they are a pain to get mounted, but they "fit" -- if you let them sit for a month to let them square-up on the wheels.

 

Just curious (not flaming, just asking)...

re>: Yes, they are a pain to get mounted, but they "fit"

If they "fit," why are they a "pain to get mounted"?

--Spike

 

Short, VERY stiff sidewalls and wheel shape on the track wheels.

 

I've mounted 275/40/17 r-compound tires on four 17x8 stock rims for autocross, so it's not an issue mounting 275s on 8.5" wide rims.

 

The wheel is 216 mm wide. The tire is 275 mm wide. Let me if the tire falls off the wheel.

 

You're a genius . . . able to convert inches to millimeters. Why didn't I think of that!? Well, you'll be waiting a long time . . . I don't recall any auto-xers in this forum having any issues with this setup.

 

Yea it will be bigger than the rim. Or it will be to small for the rim. Everyone has OPINIONs $hit the dub guys thro 105's on 9" rims. Some people are to conservative. I plan on running 265 on all fours on my track rims. I want to see if I can get another set of rear rims. FOr the same on all four corners for rotating purposes. Youll be fine

Chris

 

It will pudge but it will work with no issues.

 

thanks guys,,,,

think might go for it, just wating for the advice of the tirerack tech

 

autocross and street tires are completely different animals, the sidewalls are significantly stiffer on autocross/track tires, so are less prone to rollover. A 275 street tire on an 8.5" wheel will have significant bulge, and while it may not physically fail, it can very easily lead to decreased performance due to excessive sidewall flex and rollover from being mounted on too narrow of a wheel.

 

I've had 275/40 street tires on my rear 8.5 since about month 7 (and 11K miles on the original 245/45s). Now, nearly two years (and several practice and rain events, not to mention another 20K+ miles), I've replaced the 275/40s -- with another set of 275/40s.