OEM C5 Z06 Wheels Test Fit 18x10.5" 275/35R18

[r0nd3L]

I got some 275/35R18 tires mounted on the OEM C5 Z06 18x10.5" ET58 wheels today. I thought the tire may be stretched too much, but it's perfect. Anyway, I wanted to see how they'd look mounted on the back of the car. First impressions, BADASS! Much nicer than 17x9.5" I tried couple months ago, those looked way too small for the car. I will probably keep these.

Here are the problems, though:

1) Tire rests against inner fender. After some banging with the hammer, it clears at static ride height.

2) Touches shock. I think won't happen once KW are installed because they don't have that big ass dust cover.

I think I will do some more inner fender massaging or get a small spacer as it looks like there is still some space to be had on the outside.

Once I get some 1" adapters I will test fit this combo on the front. I'm skeptical at this point, but who knows.

http://manizone.com/gto/z06_back/1.jpg

http://manizone.com/gto/z06_back/2.jpg

http://manizone.com/gto/z06_back/3.jpg

http://manizone.com/gto/z06_back/4.jpg

http://manizone.com/gto/z06_back/5.jpg

Winter vs Summer setup :)
http://manizone.com/gto/z06_back/6.jpg

My floor jack failed, had to use stock one :bomb:
http://manizone.com/gto/z06_back/7.jpg

[brazenorange06']

looks great man! beautiful! That almost looks like what should have come on our cars.

[Lorider680]

Is the correct jacking point?
F

[99socalfrc]

What are you going with on the front? Any chance a wider tire will fit? (How much massaging was required)

[r0nd3L]

Is the correct jacking point?
F

That's factory jack point. There is a notch on the pinch weld.

[r0nd3L]

What are you going with on the front? Any chance a wider tire will fit? (How much massaging was required)

I will see how these fit on the front. If there is no way they will fit, I'll run 17x9.5" Z06 wheels with 275/40 in the front.

I think 285 would work in the back, but I just need to figure out what's a good way to gain more clearance on that stupid inner fender. Would be nice to find somebody who can weld so portion could be cut out and welded back in.

[99socalfrc]

I am dying to try and squeeze a 305 M/T Drag radial under there. What type suspension mods do you have, lowered? Bags? etc.

[r0nd3L]

I am dying to try and squeeze a 305 M/T Drag radial under there. What type suspension mods do you have, lowered? Bags? etc.

All stock. I have KW V3s and Noltec offset strut mounts ready to go in, though.

[99socalfrc]

Trying to talk myself into widening the stock 18's to 9.5 wide,maybe move the lower shock mount inward, and start beating on the inner fender, maybe drag bags too. That 10.5 wheel looks good under there, that is a 52 mm offset?

[r0nd3L]

Trying to talk myself into widening the stock 18's to 9.5 wide,maybe move the lower shock mount inward, and start beating on the inner fender, maybe drag bags too. That 10.5 wheel looks good under there, that is a 52 mm offset?

ET58.

[99socalfrc]

So that means it is a 58mm offset?

[flink]

http://manizone.com/gto/z06_back/3.jpg


A good way to fix that rub point (tune: "I rubbed everywhere, man, I
rubbed everywhere") is to get a large adjustable wrench, grab the
weld with it and bend away.

But yes, it looks like a little spacer is needed.

If you're planning on doing rear control arm bushes, do 'em now. The
stock rubber bushes allow so much movement back there that you
end up having to do much more clearancing than you expect.

I found that my driver's side wheel had too much toe. Cranking that back
half a degree helped with clearance too.

But... is it reeeeeeeeealy worth it, running 10.5's? It's still a 275mm
tire and you have clearance issues and you lost rotatability?

[d_schist]

Put the KW's on already :oldfogey:. You've had those things for months it seems. Trust me you will wonder what took you so long or at least put the rears on it takes an hour with the crappy spring compressor.

[r0nd3L]

Put the KW's on already :oldfogey:. You've had those things for months it seems. Trust me you will wonder what took you so long or at least put the rears on it takes an hour with the crappy spring compressor.

Have to wait till winter is over :(

It sucks, but they would be useless in winter anyway, especially with those spongy winter tires haha.

[r0nd3L]

A good way to fix that rub point (tune: "I rubbed everywhere, man, I
rubbed everywhere") is to get a large adjustable wrench, grab the
weld with it and bend away.

But yes, it looks like a little spacer is needed.

If you're planning on doing rear control arm bushes, do 'em now. The
stock rubber bushes allow so much movement back there that you
end up having to do much more clearancing than you expect.

I found that my driver's side wheel had too much toe. Cranking that back
half a degree helped with clearance too.

But... is it reeeeeeeeealy worth it, running 10.5's? It's still a 275mm
tire and you have clearance issues and you lost rotatability?

I know, but damn do they look so much better than 17" I tried. But I would still be able to rotate if I have same setup on the front! Nice to dream sometimes :)

[99socalfrc]

See that's always my thought, I can fit 265's on my oem 18's with just pedders drag springs, (there are guys running the 275 BFG on this combo) the only way I would start mashing stuff up is to get the big meat on there.

[99socalfrc]

I know, but damn do they look so much better than 17" I tried. But I would still be able to rotate if I have same setup on the front! Nice to dream sometimes :)

Very curious to see the 18" and 17" combo, I agree for some reason the stock 17 is the only one that looks ok on the back?:confused:

[d_schist]

Have to wait till winter is over :(

It sucks, but they would be useless in winter anyway, especially with those spongy winter tires haha.

Ahh....I forget that in other parts of the country it snows during the winter. It did snow here 1 day this year and it actually stuck to the ground for a few hours. Snowmen and snowball fights were abound.

[05 goater]

damn that looks sick!!! . just pound back the lip that is touching point?

[LaTechGTO]

I was thinking ... you put a spacer in there, massager the inner fenders, and shave down the lip on the outer fender (looks like you still have plenty to shave off....), then you should be good to go!

[GeeTeeOh!]

'tis nice

[REBinc]

I like the wheel in the front.

[Crisis]

Looks pretty good.
Keep us posted on how this goes. I'm looking at going the same route with the same rims in the back but with 295/35 or 295/30 rubber to get a bigger foot print. From the pictures it looks like you would only need a 3-5mm spacer and as has been said before a little fender cutting and inner well massaging. Otherwise the ET looks perfect in terms of how the wheel looks on the car. I would try and not use spacers at all.. Just clearing the inner fenders and strut. Polly bushings everywhere of course.

For the fronts I have also been looking at the 17" Z06 wheel but with 255/40 tires.
I just hate to run thick spacers... 5mm whould be the max for me so I'm looking at running coil overs up front or if I could get a 17" wheels with a smalle ET.

[r0nd3L]

Looks pretty good.
Keep us posted on how this goes. I'm looking at going the same route with the same rims in the back but with 295/35 or 295/30 rubber to get a bigger foot print. From the pictures it looks like you would only need a 3-5mm spacer and as has been said before a little fender cutting and inner well massaging. Otherwise the ET looks perfect in terms of how the wheel looks on the car. I would try and not use spacers at all.. Just clearing the inner fenders and strut. Polly bushings everywhere of course.

For the fronts I have also been looking at the 17" Z06 wheel but with 255/40 tires.
I just hate to run thick spacers... 5mm whould be the max for me so I'm looking at running coil overs up front or if I could get a 17" wheels with a smalle ET.

Yes, 255/40 was in my mind too. It would have equal amount of stretch stretch as the rear and look the best probably. But I'm doing this more for more grip so I want widest tire possible.

Once I do some test fitting I'll know for sure which size to go with, though.

And the reason I want adapters for the front is to trully eliminate any possibility for vibrations. Adapters will convert 5x120.6mm bolt pattern to 5x120mm and GTO's center bore to Corvette's size.

[Crisis]

Yes, 255/40 was in my mind too. It Adapters will convert 5x120.6mm bolt pattern to 5x120mm and GTO's center bore to Corvette's size.

I was looking at just centering rings for the bore size.
the 0.6mm doesn't affect anything.. I ran BMW 120 * 5 rims on my Firebird. Topped the thing out at 270kmh (or about 168mph) with 0 vibration (I do have an upgraded driveline).

[r0nd3L]

I was looking at just centering rings for the bore size.
the 0.6mm doesn't affect anything.. I ran BMW 120 * 5 rims on my Firebird. Topped the thing out at 270kmh (or about 168mph) with 0 vibration (I do have an upgraded driveline).

Nice to hear you had no problems. But if I'm getting custom adapters, might as well make them to exact tolerances, right?

[Crisis]

True.. I just had a friend machine me the 4 rings.
I always have horrow pictures of wheels flying off with spaces. Many do use them so I guess theirs not a big risk involved doing it right.

[ericwilloughby]

I've been looking at the z06 wheels also. Was afraid the 10.5 wouldn't work though. So it rubs the inside but not the quarter panel on the outside? How much clearance there?

[ericwilloughby]

Well, how much clearance on the outside?

[r0nd3L]

Well, how much clearance on the outside?

I haven't tested and won't until spring time comes. I need to take spring out to test full compression clearance. From the looks of it, looks like there is some room on the outside.

[St.Mary]

Any chance you could just stick a tape measure, stick it right near the outer wheel/fender lip just so we get an idea of how close the tire is to the fender?

[r0nd3L]

Any chance you could just stick a tape measure, stick it right near the outer wheel/fender lip just so we get an idea of how close the tire is to the fender?

I can try this weekend.

[Mikey340]

Nice job Mantis!
Can't wait to see this completed if ya need a hand give me a call.
Mike

[r0nd3L]

Nice job Mantis!
Can't wait to see this completed if ya need a hand give me a call.
Mike

Come March and I'm putting everything on. I don't care if there's still snow, I won't be able to wait any longer!!!!

[Trents_goat5.7]

looks good.

[GTO nate]

looks really good!! I got flamed for putting a 10.5 wheel on the rear of mine, I think mostly because I'm running a 265, and not the 275 like every one else. but oh well, those wheels look awsome with the lowered stance you got, on the red car. get some more photos soon!!

[BiggVigg06]

Do you know what the offsets are on the front Z06 wheels?

[r0nd3L]

Do you know what the offsets are on the front Z06 wheels?

They're 17x9.5" with 54mm offset. I ran around with those mounted on the back with 265/40 tire and had no rubbing what so ever. My fender lips are grinded, but I think they'd clear with full OEM lip. They really do have a perfect offset. I was going to run them all around but they looked awkwardly small on the back of GTO.

[BiggVigg06]

So how do you think they will fit up front. I guess you need a pretty big spacer. To bad they aren't 17x8.5" with a 40et up front. They would fit perfect.

[r0nd3L]

So how do you think they will fit up front. I guess you need a pretty big spacer. To bad they aren't 17x8.5" with a 40et up front. They would fit perfect.

The wheels in the original post almost fit the front. Pokes about 15mm. The 9.5" should be spot on.

http://www.ls1gto.com/forums/showthread.php?t=2882 67

[St.Mary]

What size spacer did you have on the fronts? I've got a set of c4 wheels for this year's autox season and I was thinking 1" adapter. Could I make .75" work? Trying to do as little fender work as possible! 17x9.5 (think 56mm offset)

[wickedgto8]

Looks decent!

[r0nd3L]

What size spacer did you have on the fronts? I've got a set of c4 wheels for this year's autox season and I was thinking 1" adapter. Could I make .75" work? Trying to do as little fender work as possible! 17x9.5 (think 56mm offset)

I haven't messed with the fronts yet. I think you'll want at least 24mm, though and maybe more if you want to dial in negative camber. Is this going to be for autox use only? If so, get wider adapter and dial in -3 camber then change to street wheels and street camber.

[ericwilloughby]

About your sig, I've been calling around about the NT-05 tires. No one knows shit about when or how much. Even Nitto has no clue. I wore my NT-01 to the cords and put on used stuff yesterday waiting to see what happens here. Any info?

[r0nd3L]

About your sig, I've been calling around about the NT-05 tires. No one knows shit about when or how much. Even Nitto has no clue. I wore my NT-01 to the cords and put on used stuff yesterday waiting to see what happens here. Any info?

Well, according to their site they should be available in February. Don't know if they are going to keep that promise, though.