12" wide rear wheels On a ZL1
 

I want to run a 20x12 43 offset on the rear. The number seem to work but i was wondering if anyone else has run a 12 and what tire size did they use? I am thinking of 335/30/20 or some 345/30/20 like cup 2s.

Good luck finding 332/30/20 tires.

The wheel should fit fine depending on what tires you put on there, it could rub on the inner fender

fixed

Cup 2 345/30ZR20
(106Y) SL
180 AA A 2,094 lbs. 51 psi 7.2/32" 33 lbs. 11.5-12.5" 12" 13.8" 12.7" 28.2" 738 FR
From Tire Rack

I'm honestly not seeing a 12 inch wheel fitting very well without sticking wayyyy out side of the fender. If you do it, be sure to post pics because a Corvette size wheel/tire would look sick on our cars.

12' wheels would look really nice.

So am i going to be the guinea pig? That's an expensive chance. But the numbers seem to all work and i have checked the clearances and its there. The front wheel is about 3 to 5 mm in and the rear is about 15 mm in from outer fender lip to rim face. with a 20x12 43 that's another 13 out, it will be close. I was also consider a 11.5 just to hit the min on a 335 tire. Whats the widest tire anyone has put on the 20x11 43 wheel? Was there any rubbing issues? Camber does come into play with these numbers.

Honestly if you can find a local guy with a GS/Z06/ZR1 body style in C6 or C7 to unbolt his and mock them up on your ZL1 you'd be able to get an idea, those are be 20x12 with 59mm offset, bolt pattern should be the same. Not 100% sure it would work at all but it's worth a shot if you can.

I know a 11" wheel will stick out the same as a 12" wheel as the 12" just adds more on the inside. This is unventured territory.

Here is my car with the OE Z28 wheels, 305/30R19 tires, and stock ride height:

http://i464.photobucket.com/albums/r...psfj7g2ev2.jpg

As you can see, this wheel/tire fitment already sticks out past the fender lip. With a 26" tall tire, it doesn't rub, but I'd be concerned that a 28" tall tire would contact sheetmetal.

Does anyone know if a 315/35ZR/20 will work on the rears of a ZL1

Yes those will absolutely work on OEM ZL1 wheels.

Z28 wheels have a different offset, i believe its,
Quote:
F 19x11ET11 (25mm further out than ZL1/1LE wheels)
R 19x11.5ET26 (23mm further out than ZL1/1LE wheels)

With a 20x12 43 offset, Thats plus 13 either way. The inside has room and it should make the outside flush or just under. I may just go wuth 11.5 43 offset to be safe. With that i can run a 345/30/20 cup 2 O.D. is 28.2 just under stock. They are on the narrow side of just 12.7 tread width. The wheel width minimum spec is 11.5.

So I ordered VS02 in matte brushed bronze
20x10 23 offset front with 285/35/20 Cup 2
20x11.5 43 offset rear with 325/30/20 Cup 2
and now I wait 5-7 weeks.