275/40 or 285/40 on an 8" wide rim

[tripower]

Is this practical? Safe? Advisable?

In several recent magazines there is a gold 65 GTO that's running 18x8 rear rims (Oasis I believe) with 295/45 tires. This got my mind thinking about issues such as tire manufacturer's recommended rim widths and such and if this was a safe practice.



I also have a 65 GTO and would love to get a 275/40 or 285/40 under the back end utilizing the AR CL205 TT2 Classics I have now. The CL205 in 18" is only offered in 7", 8" or 10" widths. I think the 10" may be too wide to clear without modifications which I don't want to do.

Thoughts? Comments? Thanks.

[Drewhelm]

The thing is....when you go down in aspect ratio the rim width has to be closer to the same width as the tire section width. For example a 295/50/15 can be mounted on a 15x7.5 inch rim. Similar to the 295/45 on the 18x8.....that's SQUEEZING it. I've seen quite a few 275/40's on 8 inch wide wheels, but a 295/40 would probably not be the best choice.

[USAZR1]

Drew's correct. I wouldn't recommend a 295 tire on an 18x8.
A 275/40/18 tire on an 18x8 is borderline but should be ok.

IMO,I don't think an 18x10 will fit,either. An 18x9.5 will fit,though.
The TT II Classic would look so sweet on a GTO that it would be worth it to me to buy 18x8's with 4.5" backspacing and then have them widened to 18x9. That would give you a 9" width and 5.5" backspacing,which would fit a 65 Goat like a glove.

[tripower]

Clint, Check out my vBGarage as I have images of my 65 with the 18x8s on it. I believe I bought them with either 4.5" or 4.75" BS as well. Do you have anyone in mind you could recommend to widen this type of wheel that does good work?

[USAZR1]

I've heard good things about this place:
Weldcraft wheel widening
(734) 420-2211
Ask for James

[novajess1972]

A 275mm wheel is perfect for the 8in wheel. My buddy just put a set on his 1964 GTO and they are the shiznit! I have 295s on my 1970 Chevelle SS, but with a 10in wheel in the rear and does it look mean!!!! My car's resto will be complete next week, but here is a pic.

[tripower]

A 275mm wheel is perfect for the 8in wheel. My buddy just put a set on his 1964 GTO and they are the shiznit! I have 295s on my 1970 Chevelle SS, but with a 10in wheel in the rear and does it look mean!!!! My car's resto will be complete next week, but here is a pic.

Can you post any pics of your buddies 64 GTO with the 275's? Thanks.

[USAZR1]

A 275mm wheel is perfect for the 8in wheel. My buddy just put a set on his 1964 GTO and they are the shiznit! I have 295s on my 1970 Chevelle SS, but with a 10in wheel in the rear and does it look mean!!!! My car's resto will be complete next week, but here is a pic.

As mentioned before,a 275 tire on a 17x8 or 18x8 wheel is not optimal but will work. However,a 275 on a 15x8 wheel will work fine. Those 295's on your 70 Chevelle are 295/50/15's,,right?

[Ralph LoGrasso]

Like Clint said, it's all in the sidewall height. The taller the sidewall, the wider you can run on a given wheel size. For example, I've got 305/70/16 on 16x8 rims on my Tahoe and they fit just fine, and are within manufacterers recommended rim widths and everything. However 275/40 on an 8" wide rim is not recommended and not very safe, IMHO.

[F70t/a]

I don't think any of those tires will look good or be safe on a 18x8. IMHO

[mnchevelle]

As long as the rim width is somewhat close the the recommended tire width it should work fine. I wouldn't go to large though. I have 275/40/18 corvette tires the goodyear eagle f1 emt on the back of a 1970 chevelle which is in the process of a restoration and they work great. Check it out at www.cardomain.com/id/mnchevelle

[Lawrence]

I found this site to be really helpful. If you scroll down theres a calculator to work out what tyres fit what size rim. Loads of useful info there too.