Derek 357i

I am looking at running 18x10 on all four corners on my c6, with 275/35/18 in the front and 285/40/18 in the rear. The wheels are +79, so i just need to determine the best offset so i can get the right hubcentric spacers.

Does anyone know their precise offset or backspace that is running this front combination?

Curt D

Plug in your numbers here.


http://www.corvettecentral.com/wheel-offset/

Derek 357i

Thanks for the response. Since i am going 1.5" wider in the front, I wanted someone running this configuration to speak to their actual offsets. I don't want any surprises on inner clearance.

Scooter70

On my narrow body C6 racecar, I run a 305 on C5Z05 rear wheels (18x10.5 +58) and it only hits the C6Z06 brake duct at full lock. You can use that as a "worst case" when comparing stock vs really wide. Using the calculator posted above or this one don't let it go farther inboard (less inner clearance) than the C5Z wheel.

For instance, stock C6 8.5" wide wheel vs C5Z 10.5" gives 27mm less clearance on the inside. Your 10" wide +79 wheel has 42mm less clearance so it would take a 15mm spacer to put it at the same place. That said, I would go a little more to gain some clearance on the inside and move the wheel out a bit to sit more flush with the fender.

16mm is about 3/8". That's a big spacer and will require longer wheel studs. I think I'd find wheels with the proper offset vs using these with a huge spacer.

z06scentair

16mm = 3/8" ?

16 x .0393" = .6288" = ~ 5/8"

Agree much to wide to run safely.

Scooter70

Sorry. I had a brain fart. You're right.

Suns_PSD

I have that same size tire (R888s which is a wide tire) on my base '08. My front wheel is an 18x10 with 7.75" backspacing. I get a bit of rubbing on full turn on my Z06 air brake ducts I added. No biggie. I try not to cut the wheel all the way to the locks in parking lots for this reason.

I run -2 camber and the wheels I would say are perfect as far as fitment goes. If I didn't run that sort of camber however they could start to protrude a bit.

Next time I buy R888s I'll go with 285/ 30 x 18s up front.

I hope that helps.

sallen619

I run the LG Challenge wheels. They are 18" x 10" in the front with a 285/35 tire on them currently. I don't know the offset of the wheels, but they fit just fine.