bobmoore2

Soon I'm going to buy wheels and race tires for my C6 Z51. I've been running 275/35-18 and 305/35-18 on my C5, and they fit very well. I'm wondering what sizes I should use on the C6 Z51. I will also have DRM brake ducts. I don't want the tire rubbing anywhere, and I still want most of the steering travel.

What size race tires do you use on your C6 - not Z06?
How do they fit in the fender wells?
Did you have to change the wheel's offset/back-spacing from the stock numbers to make them fit? (Stock offsets are 58mm for front and 79mm in back.)

I'm probably going to keep using 18" wheels front and back, because my scrubs supplier has lots of 18" tires at a great price.

Bob

gkmccready

If you stick with 275+305 your C6 Z51 should be happy. CCW can set you up with an 18x10+18x11 set up that would work very well for those sizes. Backspacing is definitely different from stock...

I have 295/30r18+305/35r18 on 18x11+18x11. I have to run a steering limiter and -2deg camber up front to get things to clear. I *think* you could go to an 18x12 in the rear if you wanted to. CCW probably has more experience now, I think I was one of the first to try the 18x11s all around.

rbl

I use C5 rear wheels for the front and stock Z06 rear wheels for the rears on my 06 Z51. No other BS needed or special alignments. Save the money for tires and beer. R-888's for tires ... 275 & 305's. Check the diameters for other tires.

C5 rears are cheap and easy to find~$150 or so. I have an extra pair of Z06 rears, both aftermarket and almost new OEM's. They aren't as cheap and hard to find. You may need a loan for the CCW's .. You look to be in the West so check around out there to avoid shipping stuff.

bobmoore2

I test fitted the race tires & wheels from my C5 Z51 onto my C6 Z51.
Fronts = 275/35-18 on 18x9.5 w/53mm offset
Rears = 305/35-18 on 18x10.5 w/53mm offset (like stock C5 Z06 wheels)

The fronts fitted the C6 just fine, but the rears stuck out of the fender by about 1 1/2 inches. Obviously the rear wheel's offset was all wrong. I've got the stock suspension with full spring travel, and I'm not going to let the rear tires destroy my rear fenders.

bobmoore2

Based on what you said and the available sizes of scrubs I can get, I would not go bigger than 275 on the front (maybe 285), and 305 on the rear (maybe 315 or 325 if available).

You said the backspacing is definitely different. Please elaborate. What backspacing (offset) are you using with your rear wheels?

gkmccready

I think it's around 8.5"-8.75"; I don't have the specifics written down. Whatever John@CCW shipped after we talked about it. Like I said, though, we talked later about doing an 18x12 and still running a 305 R888 for a dual purpose tire.

FWIW, the 295 and 18x11 *barely* rubbed the fender at full compression, and now that I have about -2deg up front it clears nicely. But it does appear to like the steering limiter to keep off the tie-rod and/or wheelhouse depending on what camber settings I have.

You'd be very happy with 18x10+18x11 with 275+305... CCW is great to work with and, IMO, well worth the price to get a proper fitment.

WNeal

I am using 315 x 18 all the way round using C5 Z06 Rear wheels.
put 3mm spacers up front and cut out just a little bit of the inner fender and the car loves it.
Also have steering stops up front to keep from rubbing in the paddock on full turns with the wheel. Really don't notice the decreased steering at all.

I have done nothing to the back and they fit fine.
just have to live with some minor mods in the front and no more rubbing.

As a bonus, I can now also rotoate the wheels around the car, add that to flipping the tires, and I get as much out of the tires as you can.

A recent trip to VIR, a good friend sent me this photo

bobmoore2

Bill,

You're the second one today who says he is using C5 Z06 rear wheels on the back axle.

When I test fitted my C5 Z06 reproduction rear wheels onto the C6, they stuck out of the fender about 1 1/2 inches. The wheels are 18x10.5 with 53 mm offset (7.25" back spacing). What is the offset or back spacing on your wheels? Do they stick out?

Bob

P.S. The stock offset on a C5 Z06 wheel is 58 mm (about 7.5" back spacing). Therefore, I must conclude that if your wheels fit inside your rear fenders, then they must have a non-stock offset / back spacing. No other conclusion makes sense to me.

rbl

Then your "repo" wheels are wrong because the OEM Z06 wheels fit just fine.

Maybe you need a special wheel for your 305/35-18 tires ........... The Z06 wheels work great with 305/30-18's.


CCW's are always a good choice though

gkmccready

My notes show C5Z rear wheel is 18x10.5 58mm offset and 7.9" backspacing. The stock C6 rear wheel is 19x10 79mm offset and 8.11" backspacing. Sure looks like the rear should fit just fine.

Call the backspacing difference a wash, the C5Z should move 0.5" further out than the stock wheel and there should be plenty of room for that?

There are a lot of C6s running around on C5Z wheels at all four corners without major issues, so it must be possible... I still love my CCW Corsairs... clearance for Wilwood SL6Rs, exact fit for the C6, wider, light, strong, ...

gkmccready

Do you just really hate CCWs or what's the deal? They fit great, work great, provide much better clearance for BBKs, etc, etc. Sure they're expensive, but if that's your beef just state it as such...

rbl

I actually did not know I had a beef and sorry you think I do. In review I think you must have missed something ... For the record, CCW's are a great product no doubt about it ... look good, feel good, work good, last forever, fit perfectly and go fast. They are also quite expensive.

What I said in the very first post was "You may need a loan for the CCW's .." This implies cost is a big factor when a very good alternative was suggested. It was just a friendly heads-up.

However, money is always the issue ... why spend what (I'm guessing) $2500 when you can get the exact same performance and reliability for $500-600 tops? If you have cash to burn then it does not matter. But I don't find myself in that position, however, so I am using the stock Z06 wheels, have been for 2 years, and they do in fact work/fit perfectly. Which is what I said without all the math.

You are correct in that several people are running the OEM Z06 wheels on all 4 corners. I think there is some slight rub at full wheel lock.

Another possibility is to use the OEM sizes and there are tires available for them now. However, OP said he wanted to buy scrubs and I doubt you will find any 19's.

It sounds lik OP has tired some China Z06 knock-offs on his C6 and because they "look" like a Z06 wheel he assumed they would fit the C6. Consequently he now thinks that the OEM Z06 wheels (I did say stock Z06 right) are wrong for the C6 .... and as we now agree, that is false. This is another reminder and a note to self ... don't offer information because someone will ultimately want to argue about it or be offended in some way. Heck, I don't even know anything about wheels in the first place!

gkmccready

Well, I apologize if you were offended, and I certainly wouldn't want to stop anybody from offering an opinion, but the little laughing icon after the CCW comments seemed to imply that you found the CCWs laughable in some way or another.

I bought the CCWs before anybody could tell me for certain if the C5Z rear wheels would fit, and after dealing with CCW, and putting on the Wilwood SL6Rs with plenty of clearance, I'm more than happy to keep recommending CCWs to people. John and Chip have been excellent to deal with, and the product is top notch.

WNeal

Hi Bob,
I will have to check on the offset etc. but they are stock C5 Z06 wheels and I use the same on all 4 corners.

I won't be up at my shop until Sunday.

I have two sets of em and have no problems at all.

Webz

I am also running 10.5 x 18's square. I have run 305/35's Toyo R888's and 315/30's Hoosier R6's. The Toyos rubbed worse than the Hoosiers. Both tires rubbed the front fender liners at full lock. I am also running an 1/8" spacer on the front but currently no rack limiter. Great set up as Bill say's. With suspension and alignment set up to match the wheel/tire combination this is a great handling approach.

Theoretical amount C5Z06 rear wheel sticks out more than C6 stock rear.
27.35mm or 1.07"