I have the original 87 IROC-Z 16" wheels. I was thinking of going with these wheels. What effect will going to a 17" wheel have on my car? How much time will it add (slower) to a 1/4 mile? http://www.afterthoughtsauto.com/zr1...ed-wheels.html These 16" are cool too. http://www.discounttiredirect.com/di...vid=002619&bp=

 

18" ZR1's are harder to find but they do make them and they look way better


18" is the way to go, 17's is to small,

I kind of wish I went 19's

my car is a fair bit slower then it was

 

I'm going to stick with 245/50 in front and maybe go to 275's in the back. The back has 255/50-16 now. That was plenty grippy with my factory L98 350 with a few mods pushing around 270HP. It won't be wide enough for good launches with my new engine in the signature.

 

I think 17's on thirdgen's look pretty good. Zr1's do look good too. I love my Ronals and the way my formula handles with them on. I never ran it at the track yet to tell if there is any difference in the times, it's an all stock LB9 so I doubt it has a huge effect.

 

I love those. They are my absolute favorite on the Pontiac. I'm probably going to get this http://www.tirerack.com/wheels/Displ...k+w%2FMach+Lip

 

I switched over to 17x8.5 wheels and 245/45/17 tires five years ago and the look improved my car.

 

I thought it was possable to change your gearing slightly once you get bigger tires so you wont lose any speed?

 

Are those 4th gen offset? The thing that makes me really love the ronals is the dish they have, you can really see it on a 3/4 view. Also you can goto a bigger wheel and not change the overal diameter of the wheel/tire.

215/65-15 on a 15x7
235/60-15 on a 15x7
245/50-16 on a 16x8
255/50-16 on a 16x8
275/40-17 on a 17x9.5
275/35-18 on a 18x9.5
295/35-18 on a 18x10.5

They are all around 26" Overall diameter, smallest being 25.7", biggest 26.1" you just loose sidewall and become less and less pothole friendly

-Jim

 

I got those on mine and i love them, im also running 255's all around .

here they are cheaper... http://www.slponline.com/browse_list.asp

 

That link goes to nothing

 

I've got 17's on my formula and I don't think i'll ever go to a smaller wheel.
I did have a set of 18" Z06 wheels but the offset on the rear wheels was a bit too positive and stuck out too much for my liking.

 

I'm going to go with the 17" for sure. It's tough to find a 275 wide tire in a 16". Every brand tire has a 17" 275 wide. I think only an inch bigger will not be a big deal on acceleration.

 

thanks.
I would have kept them had I been running spacers in the rear, then I could have had them cut down a bit to put the wheel into the fenderwell.
since I have the LS1 rear, there is nothing short of widening the body or narrowing the rear end, which both would be expensive.
18x9.5" in the rear would have worked as well, but I decided to stick with ZR1's.

 

O sorry here you go these are the ones i have now...


http://www.slponline.com/view_product.asp?P=81001