Question about wheels
Safety Car
Joined: Oct 2006
Posts: 3,993
Likes: 9
From: Gig Harbor WA
I just went through a ton of this here and the first tire in your pic looks to be a TT D model. And those have 4.5 inch backspace and rub on some cars and suck the tires a half inch farther inside. A regular TT wheel is 4.07 in back and a 255/50-17 is exactly the same demensions as the 255/60-15, it will work with stock suspension and not suck in the wheel. Got a new set today, in the garage. I don't know about the rear size, I went the same on all four corners.
Here's a picture.
http://www.mhtwheels.com/wheel.cfm?cat=801
Racer
Joined: Nov 2011
Posts: 261
Likes: 1
From: Montgomery TX
Thats a perfect combination for your car. That's the combination I ordered except I am going with US Mags which are very similar to TT M's. The II's have a more modern look with less wheel lip. I personally like a more classic look but wanted the larger wheels and high perf. tires. The wheels I tried on my '81 from a fellow vette owners '82 were 18x 8 TT II's but he has 18 x 9 with 275 on the back with 5" BS and had to use a 1/4" spacer to clear the trailing arm. The 275's are .75" wider and .75" taller than the 255's. Even with the spacers he still gets some rubbing when the tires flex. He is going to install longer studs and 1/2 spacers which is not recomended but cheaper than offset Trailing arms.
I know of another 82 running some unidentified rims with 275 40 18 with no clearance issues but I dont know the BS they are using, he didn't either since he bought it that way. Every Vette is a little different. They weren't designed on computers and assembled with robots back then.
The TT II's are 4.5 BS not 4" so it will pull the wheel inside the WW 1/2" but with the wider tire it fits just about perfect.
I know of another 82 running some unidentified rims with 275 40 18 with no clearance issues but I dont know the BS they are using, he didn't either since he bought it that way. Every Vette is a little different. They weren't designed on computers and assembled with robots back then.
The TT II's are 4.5 BS not 4" so it will pull the wheel inside the WW 1/2" but with the wider tire it fits just about perfect.
Racer
Joined: Nov 2011
Posts: 261
Likes: 1
From: Montgomery TX
The 18 x8 with 255's will only add 4 - 5 lbs per wheel over a stock 15" wheel with 255 60 15's. A small price to pay for real Z rated perfomance tires instead of the 15" passenger car tires. Remove the spare and you'll make it up.
Instructor
Joined: Dec 2010
Posts: 169
Likes: 1
From: Merritt Island Florida
http://forums.corvetteforum.com/c3-g...res-weigh.html
18 x 8 Coys look like +11 lbs. each...
Sorry if I'm hijacking the thread Scott, it's just that I see folks spending lots of money on light weight brakes, control arms, etc. then bolt on what looks like heavy wheels. There's just not much info on this.
Carl
Drifting
Joined: Aug 2009
Posts: 1,635
Likes: 8
From: Enid Oklahoma
Thats a perfect combination for your car. That's the combination I ordered except I am going with US Mags which are very similar to TT M's. The II's have a more modern look with less wheel lip. I personally like a more classic look but wanted the larger wheels and high perf. tires. The wheels I tried on my '81 from a fellow vette owners '82 were 18x 8 TT II's but he has 18 x 9 with 275 on the back with 5" BS and had to use a 1/4" spacer to clear the trailing arm. The 275's are .75" wider and .75" taller than the 255's. Even with the spacers he still gets some rubbing when the tires flex. He is going to install longer studs and 1/2 spacers which is not recomended but cheaper than offset Trailing arms.
I know of another 82 running some unidentified rims with 275 40 18 with no clearance issues but I dont know the BS they are using, he didn't either since he bought it that way. Every Vette is a little different. They weren't designed on computers and assembled with robots back then.
The TT II's are 4.5 BS not 4" so it will pull the wheel inside the WW 1/2" but with the wider tire it fits just about perfect.
I know of another 82 running some unidentified rims with 275 40 18 with no clearance issues but I dont know the BS they are using, he didn't either since he bought it that way. Every Vette is a little different. They weren't designed on computers and assembled with robots back then.
The TT II's are 4.5 BS not 4" so it will pull the wheel inside the WW 1/2" but with the wider tire it fits just about perfect.
Drifting
Joined: May 2005
Posts: 1,968
Likes: 44
From: East TN
I have VBP performance plus suspension with offset trailing arms and run 17x9.5 and 275/40 ZR 17 tires and 2.5" wheel adapters all around. Could have gone with 18" on the back no problem. But, I prefer to be able to rotate the tires. Tires do not rub anywhere. 
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Thread Starter
Le Mans Master
Joined: Mar 2008
Posts: 5,948
Likes: 72
From: Oxford MA-----You just lost the game!!!!
I'm sure it depends a lot on the choice of wheels, which is what I'm interested in. Searching past threads doesn't come up with much, did find this:
http://forums.corvetteforum.com/c3-g...res-weigh.html
18 x 8 Coys look like +11 lbs. each...
Sorry if I'm hijacking the thread Scott, it's just that I see folks spending lots of money on light weight brakes, control arms, etc. then bolt on what looks like heavy wheels. There's just not much info on this.
Carl
http://forums.corvetteforum.com/c3-g...res-weigh.html
18 x 8 Coys look like +11 lbs. each...
Sorry if I'm hijacking the thread Scott, it's just that I see folks spending lots of money on light weight brakes, control arms, etc. then bolt on what looks like heavy wheels. There's just not much info on this.
Carl
Keep the shiny side up!
Scott
Pro
Joined: Dec 2006
Posts: 695
Likes: 5
From: tx
Wow, really? How about not being able to find good/great/excellent rubber in 15"? When driving hard in an autocross or on a road course, the 15" rubber just is too hard, plus the footprint is a bit smaller. In addition, wheel offsets just aren't available in many 15" wheel styles to allow the rubber to be in the fenderwell as opposed to hanging out - 70's style.
Instructor
Joined: Dec 2010
Posts: 169
Likes: 1
From: Merritt Island Florida
I fully agree that 17" or 18" rubber is the way to go for handling and modern looks, but I would like to choose my combination wisely rather than just what looks good.
Coys Wheels responded with the following regarding weights:
26 lbs on 17x8 28lbs on 18x8 30 lbs for 18x9.5
Carl
Coys Wheels responded with the following regarding weights:
26 lbs on 17x8 28lbs on 18x8 30 lbs for 18x9.5
Carl
Melting Slicks
Joined: Mar 2007
Posts: 2,520
Likes: 11
From: Hinckley OH
18" on the front will allow a bit wider tire without hitting the lower ball joint since it's inside the wheel. Can't go with any wider than 8" wheels and a 275 tire becoause they will start rubbing elsewhere. In the back an 18 x 9 with 4.5 BS and a 275 tire will fit with no mods on most C3's. The parking brake bracket will be inside the wheel and don't need to be cut off and relocated to the top of the trailing arm.
Please note I say Most C3's. Every one has slightly different geometry and what might clear on one may be tight on another.
Best thing to do is find another C3 owner locally with custome wheels buy him a six pack to come over and pull one of his wheels and try it on your C3. Saves a lot of hassles.
I found 18 x 8 with 4.5 BS US Mags and TT M's will fit with no clearance issues with 255-45-18 front and 275-40-18 rear. Diameters are almost exactly as stock, fronts same width, rears are an inch wider.
Please note I say Most C3's. Every one has slightly different geometry and what might clear on one may be tight on another.
Best thing to do is find another C3 owner locally with custome wheels buy him a six pack to come over and pull one of his wheels and try it on your C3. Saves a lot of hassles.
I found 18 x 8 with 4.5 BS US Mags and TT M's will fit with no clearance issues with 255-45-18 front and 275-40-18 rear. Diameters are almost exactly as stock, fronts same width, rears are an inch wider.
