502Stingray

Hey all,

Ive tried doing a bit of searching but no topics cover what Im having a problem with. Im runing my 73 Stingray at Autocross events and I just recently started running into problems that ive either never noticed or that just came up.

While going hard around turns, the yoke will walk out of the diff, causing my splines to shear and my spider to be destroyed, I have a YouTube video posted to show you exactly what I mean, watch at 1:22 and 1:42 how the yoke will walk out of the diff due to the severly changed chamber.

Now my question is, what can I do to avoid the top chamber to change that severly? Ive looked into the sharkbite systems but they dont eliminate my problem, Ive looked at a few others but they dont address the top chamber change, I already have the VBP race brace under there but it still doesnt solve the problem. I dont exactly want to put in a racing 4 link suspension that costs tons of money.

Also, I heard that some there are billet parts available for our C3 diff, like a billet yoke and billet spider gears, who sells them? I dont want to put OEM parts back into my diff, now its apart, I figured its time up upgrade, especially with my 502 in there making 600 rwhp.

Thank you for your input, sorry for the long topic

YouTube link: Watch the yoke by the pumpkin at 1:22 and at 1:42
http://www.youtube.com/watch?v=FIFZMa1pyX0

gkull

I just did my rear end and I would say that you probably have one or maybe even two problems.

the stock yokes ends ware off sometimes clear past the C-clips. I bought the custom hardend yokes from Mid-America for something over $500 a pair about 12 years ago "Great investment"

Your second problem could be the posi unit its self. Especially if it is an Eaton cone type. The interior metal just wares away and you end up with yokes moving in and out.

I use www.tomsdiferentials.com posi unit and they are about $800 I also have the aluminum disks to hold the rear end cross member. I use "Smart Struts" to limit camber change during the verical travel of the rear wheels. I was using a 500 pound custom rear steel spring and just now lowered it to only 420# mono.

moonsteel

does the dragvette setup help at all?

Hauq`

Wow, that is impressive chamber change. Gkull is right on that your yolk C-clips, are broke, or warn off. When you jack up the rear of the car and grab to top of the tire and pull does it move that much. I'm a little surprised that you were able to pass tech inspection. When my axles show out of tolerance movement I'm going to fab up some upper links for a 6 link and remove the c-clips and movement all together.

Also as an observation it looks like you could use some longer spring bolts, if they don't interfere with the tires, so that your axles are parallel to the ground at rest. That way as the body roles with the turn the chamber, top of the tire, would be pulled in.

Jim_Harrison

You are mssing at least the Driver side C retaining clip. Interesting as there was a big post on this issue a few months back with some forum members insisting that that a clip missing wouldn't cause a problem.

Gale Banks 80'

The Clip Missing guys wern't Autocrossing.....

texaswilkins

Best video I've seen in a long time. I had no idea the suspension moved like that. Your car also sounds pretty good.
Bill

crf311

Great video. By the looks of it you may be missing the c clip as others have stated. also I would check out the bushing on the trailing arms, they may need changing. Looks like you are getting some serious tire roll, you may want to try some low profile tires. imho

v2racing

It does exactly what I and some other guys said they would do in hard corners contrary to what a couple guys were trying to prove with CAD drawings!

Great video!

Sorry your having a problem though.

tracdogg2

You could just replace the spiders and stub axles but this would be a good time to upgrade to Tom's KA 1350 c-clip stub axles and 30 spline spiders. Also add the oversize cross shaft. But it does require a bit of machining.
Mike

forvicjr

Ya, I remember this one well. Wonder if any of THOSE guys will speak up now that they have been proven wrong. One even said the preload was so much,the car would slide before having enough force to pull out on those halfshafts! Think ill dig that thread up and post this thread to see what a responce I get.

PeteZO6

I can't offer anything to help your problem but I do want to say that is the est suspension video I've ever seen. It sure answers a lot of questions and maybe puts some bench racers back on the trailer.

Pete

hugie82

That's one way too check out a problem LOL
That video was so good, I had too watch it twice

pauldana

I feel vindicated....GREAT video


put in the c clips

Clams Canino

I was also on the team that siad you needed the clips. Great Vid!! I agree with the rest of them here - new hardened stubs and new clips.

I have a question? What rear spring is that? Brand and weight?

-W

502Stingray

Thank you all for your comments and responses! I have to say its the friendliest forum ive been on, Im also on LS1GTo.com and its a bunch of "I know it better"

Gkull thank you for the Link, that helps me alot Im gonna call him up tomorrow to find out prices on the diff, I think Im gonna buy it along with the stubs that ecklers sells http://www.ecklers.com/corvette-diff...1963-1979.html are these the ones you guys are talking about?

Hmm what is the price range of that? my total budget is about 1500 bucks
By the way, where can i get the better spiders from? I did a google search and ended up with 500 links, do you have any personal suggestions?


I did see that post, but I didnt want to get involved with the discussion

v2racing

Here is the second round of the thread that hotly addressed this issue. I didn't bother to jump back in the second one. The first was enough. The first one that the drawings were posted in got deleted suddenly back then.

http://forums.corvetteforum.com/c3-t...-rear-end.html

Clams Canino

Bumping the question

wombvette

It is interesting to me that it actually pulls out on the left shaft when in a RH turn. Lots of upward push in the suspension plus the inward force on the tire contact is rotating around the strut joint to pull the shaft out. It would be interesting to note how much play is in the trailing arm bushing.

502Stingray

Hey sorry I knew I forgot something, this is the Mono Spring I got from VBP, with the Poly Bushings, I used the 420 spring since like AutoXing

http://www.vbandp.com/C2-C3-Corvette...y-1963-77.html

Ecklers sells one aswell, a friend of mine has it in his 68 and he loves it, I took his out for a AutoX hotlap and it works just as fine as mine. When we installed it i was impressed as to how light it is compared to mine from VBP

http://www.ecklers.com/corvette-mono...1963-1978.html