Pontiac GTO Forum banner

1 - 7 of 7 Posts

·
Registered
Joined
·
1,451 Posts
Discussion Starter #1
I want to buy a set of rims/tires just for the track and am having a hard time coming up with the right rim. I talked to Summit Racing last night and he said they don't have anything listed under 5x120mm bolt pattern for starters, but he found a close standard measurement that "must be what they're using for the 5x120mm". Anyways, I want a 9.5" wide rim and he said they don't have them in a 15" size, jumps from 8 to 10. I told him 8 is what I have now and a 10 won't fit. So he finds a bunch of 16" rims that are 9.5 wide and asks me what offset.

I've searched 3 different forums and even asked a question on the "epic fail" forum and haven't gotten the right answer. I'm just looking to spend 150-200 bucks per rim on a set of cheap aluminum 16" rims and can't believe 1000 people (or more) haven't done this before me. Sigh... Any assistance would be greatly appreciated. And YES, I used the "search" button on this website as well :rolleyes:.
 

·
Registered
Joined
·
105 Posts
contact diamond racing. they'll build you a wheel to order. your exact measurments.

I went through the same search and went with a weld draglite 15x8 5.5bs because the extra wheel width doesn't really buy you anything in a drag race. Other than a fender roll to clear a 275, it was a bolt on process.

the "close" measurement is 5x4.75 which is an absurdly common GM pattern.
 

·
Former Moderator
Joined
·
4,081 Posts
Here's a calculator to help with selection. IMHO it's worth it to get a 15" as the extra sidewall helps with the shock of launch. The stock wheels are 8" wide with a 48mm offset so you can play with those numbers or try different width wheels. Wider wheels should have a bigger backspace altho with rolling you can add to the outside too. A little too deep of a backspace can be fixed with ARP studs and wheel spacers. Too little of backspace can work with rolling/grinding or more severe drag bags to jack up the back end to clear the fenders.

Roughly the BS you would like:
8" would be 5.5" to 6.5" BS (6.38" is stock) (Some 8"sSummit Racing SUM-521-5862PS - Summit Racing® Fast-Five Polished Wheels - Overview - SummitRacing.com)

9"-10" would be 6.5" to 7.5" BS (some 9"s Center Line Wheels 005907547 - Center Line Wheels Convo Pro Polished Wheels - Overview - SummitRacing.com)

A small difference from ideal of up to an inch difference BS should be fairly easily accommodated.
 

·
Registered
Joined
·
24 Posts
Hmmm this is very interesting .......... Soooooo your saying that a 15x10" wheel with a 6.5" back space will fit on a GTO ???06 GTO ??? Has anyone done this before ??? I'm getting really excited here ..... I have my spare set of rear wheels off my chevelle just sitting in my garage taking up room .and they are 15x10's with a 6.5 back space but with 29 x12 Hoosier slicks on them though lol. Thats easily fixed . Man if these would fit that would be awesome to have my Bogart Drag On Star 3's on my 06 GTO .
 

·
Registered
Joined
·
105 Posts
7.5 on a 10" would be preferred. I think 6.5 would poke pretty badly. You could try it, but I don't think you're going to like the result.
 
1 - 7 of 7 Posts
Top