C5 wheels on C3...help!

[randylindberg]

I'm trying to find out if anyone has put C5 wheels on a C3? I've seen a pic of a car with them, but am unsure what all is involved. Vette brakes makes spacers and offset trailing arms, but they don't know what size spacers will work...anyone done it already?

[patsnitrovette]

your best bet is to call vette brakes and ask them what size spacers you need,i was looking into putting z06 rims on my 73.You shouldnt need offset trailing arms just the spacers.

[Last Ride]

Which C5 wheels were you wanting to run? It might be cheaper to buy a set of custom wheels made specifically for the application.

[randylindberg]

Well guys, here's what Vette Brakes says: "I don't have much on the C-5 wheel fitment but most likely it will require offset trailing arms. At 56 mm offset it is the same as a grand sport wheel and would require a 2 2/4" adapter on the front. The rear at 65mm would require that you move the wheel inward and possibly use the 2 3/4" or the 3" adapter." I am a bit fearful of using that large an adapter, but maybe it's O.K. I never thought about custom wheels...just figured it would be $$$$! If you know of a good source, let me know!

[Last Ride]

Custom wheels aren't ultra expensive. Many of the companies making high end wheels for the C5 can make the same thing for your C3, but those ARE expensive, generally speaking. I know American Racing makes custom offsets for many of their wheels such as the Torq Thrust II in various sizes. I even know of a guy running 20's on his C3. Fellow forum member 69MyWay posted this website in another thread: www.hvydeez.com I called and talked with Dave. They can make any wheel on their site custom fit to the car. The widest you can go in the rear using stock flares and TA's is 18x9. I was thinking of running 18x9 on the rear and going 17x8 up front. For that combo shipped to my door with Nitto tires, was around $2300. Not bad at all. In any case, good luck on whatever you decide.

[Evolution1980]

I'm kinda fuzzy on this whole thing too. Set me straight, if I'm not already... actually, rather than me say what I think everything is, how about someone just explain wheel spacers and offset TA's... please? Thanks in advance...

[pmazza]

I have a set of '98 Camaro SS 17x9's w/50mm offset. I used a VBP 2 1/2" spacer all around and have no clearance issues at all. This spacer width effectively centers the wheel offset again just as the stock 15" wheels were. Performance has been great, the spacer tradeoff is some additional load on the bearings. Offset arms probably are not necessary, just relocate the ebrake mount, not sure as I have a 5 link rear setup. Tires, wheels, spacers where about $1300 total. SLP makes an affordable set of 5 spokes like these.

Corvette 17x9.5" ZR1 style wheels have 56mm offset I believe so you could probably stay with a 2 1/2 or use a 2 3/4" spacer.

Phil

[randylindberg]

Phil, your car looks great! That's about the exact look I'm going for. I am hoping to run 18's on the rear, but if all you had to do was use spacers that's perfect. I should likely replace my trailing arms due to corrossion but maybe I can at least get the new wheels on to see how they look! Also, has anyone replaced their trailing arms? How hard is it?

[69MyWay]

Originally posted by Evolution1980
I'm kinda fuzzy on this whole thing too. Set me straight, if I'm not already... actually, rather than me say what I think everything is, how about someone just explain wheel spacers and offset TA's... please? Thanks in advance...

The 84 to present vettes have a positive offset. This means that the point of the wheel that bolts to the hub bearing is more outward, and the rim itself is more flat looking (less dish). The pre 84 vettes have a negative offset meaning the bolt hub portion of the rim is closer to the inside of the car and thus you have a more deep looking dish to the rim. For example, my back wheels on my 69 are EXTREME deep dish.

Now, the adapter/spacer is like a thick washer drilled out to offset you wheel studs and line up new wheel studs for the replacement rim. It "pushes" the offset of the C3 out so that it mates up with the mounting zone found on the newer cars.

It just so happens that the last gen F body and Vette can interchange wheels as they use the same basic offset.

So, that means on the C3, you can run the F body wheels or Corvette wheels as long as you install a spacer kit to move out the mounting point to a more positive offset. Also, 84-87 Vettes have less offset than 88-2003. So, if you happen to get a set of stock or custom wheels that came off a 84-87 you have to specifically get adapters for those year wheels to go on your C3.

On the trailing arms (yes, they are hard to replace as 99% of the time the mounting hardware has rusted solid, and you end up with a full rebuild of wheel bearings, e-brakes etc). The stock rear trailing arms would be that bar like thing that comes out of the frame just behind the doors and reaches to the wheel. This is the pivot mount for the whole rear end. It has a bushing up in the frame and you set the toe on the alignment by stuffing shims in and out of each side of that bushing. The other end of the arm supports the wheel bearing, shock/spring mount, and wheel. The stock unit runs the e-brake cable on the outside upper part of this trailing arm. If you go with a more positive offset rim and start pushing the inner part of the rim closer to the frame of the car you can end up rubbing the e-brake cable. Most people just cut the e-brake cable mounts off and push it aside as the e-brake does not work anyway. Others will weld the tabs back on further inboard to clear the wheel. Finally, others will go with aftermarket trailing arms that have a offset cut in them and the cable mount relocated so that you can squeeze another inch of rim in the car without hitting anything.

Consider this. The C4 rim is 9.5 inches. That means lip to lip it is about 10.5 inches wide. Your stock C3 wheel is 8" which means lip to lip it is 9" wide. You can gain 1.5 inch of rim with the C4 wheel and spacers. That 1.5 inch has to go somwhere. In this case the spacer will help split the difference so that you gain a little outbound and inbound width.

I know several people that have done it on stock trailing arms and have had no problems. Now, if you go to ZR1 rear rims. Those are 11" wide or basically 12" wide lip to lip. These are going to give you some trouble if you don't mod the trailing arm and maybe even trim the fender lip a tad.

Hope that helps.

[Evolution1980]

(Trailing Arm = "TA")

First, I have heard that wheel spacers are not highly regarded. And that they should only be a last means of sorts, as it puts a lot of stress on the spindle or wheel bearings or something? Are there times when it's definitely advised NOT to use them?

Offset TA's... I would assume that the main location (or the distance to) where the half-shaft meets up to the TA or spindle assm doesn't change? That being the case, what DOES change then on offset TA's versus standard TA's?

[69MyWay]

Originally posted by Evolution1980
(Trailing Arm = "TA")

First, I have heard that wheel spacers are not highly regarded. And that they should only be a last means of sorts, as it puts a lot of stress on the spindle or wheel bearings or something? Are there times when it's definitely advised NOT to use them?

Offset TA's... I would assume that the main location (or the distance to) where the half-shaft meets up to the TA or spindle assm doesn't change? That being the case, what DOES change then on offset TA's versus standard TA's?

The only thing that changes is they are stronger than stock, and you can run a wider tires. The actual offset of the car and or distance from one wheel to the other does not change. The offset arms have a zig zag in them instead of being straight to allow room for the tire to go inbound towards the center of the car.

[Ken]

Originally posted by Evolution1980
[B... wheel spacers are not highly regarded. ... should only be a last means of sorts ... advised NOT to use them[/B]

Andre, as a rule you want mating surfaces to have as few separate parts as possible. Spacers could just add to possible adverse consequences. Therefore, if you can avoid using spacers it is better to not use them, and they are illegal in some classes of racing.

_ken

[Evolution1980]

Originally posted by 69MyWay
The offset arms have a zig zag in them instead of being straight to allow room for the tire to go inbound towards the center of the car.

That's what I was looking for! Thanks!

[KANE]

You really have two choices if you want those wheels- modify the suspension to allow use of the factory wheels and have it resemble one of those custom C2s.... or modify the wheel.

If you want to spend the money....and..... REALLY REALLY REALLY WANTED THAT STYLE OF WHEELS... would be to have them modified to move the mounting surface closer to the back side of the wheel. That will take ALOT of cash though. I'm not covinced it would be worth it. However... there maybe some aftermarket shop tha can custom cast what you want. Again.... lots of cash.

Now, there are a few companies that make 18in IROC wheels. They fit NICELY under the C3s. Although CAMAROS can run VETTE wheels... I think its a blasphemy to the opposite. You may not go to heaven for that one!

SPEAKING OF BLASPHEMY-
How do you know God drives a Vette? THE SKY IS CORVETTE BLUE!!!

- just like the the '78 Corvette blue!!!
- or the L-48 blue
- or the BLUE FLAME blue





I promise I'll stop!!!