Part 14 – Rear axle Bracing

[RJacobsen]

After building the reinforcement plate for the rear lower control arm brackets, I decided to make some changes to the way the rear axle was held in place. The standard arrangement is that the center section is attached to the frame with 4 bolts at the top and stabilized with a brace from the rear main frame that attaches to the lower control arm pivot shafts. The original brace is in the next picture.



I redesigned the rear brace so that it attaches primarily to the new reinforcement plate and also to the control arm pivots.



Here’s how it looks installed.



I then made a similar, but shorter brace to go in front of the center section.



This picture shows the bracket mounts that are welded to the frame, they are tapped for the mounting bolts and located low enough to clear the rear stabilizer bar.



Here are a couple pictures of the front brace installed.

[RJacobsen]

Both braces installed.



After I thought I was done I realized that some hard cornering could produce a lateral load on everything, so to help with that I added some webbing to the front brace.



I’m pretty sure this will hold everything in place, and maybe it’s a little over-engineered, but I did come across a thread from a forum member that had broken all but one of the upper mounting bolts so I can’t see that this won’t help.

To be continued….

[Slither]

maybe it’s a little over-engineered...

What do you mean... over-engineered? Is that possible?

This will certainly remove the potential of the original to flex! (Not that it would.)

I like it Rod, nice work.

[weaver]

Who was the member that broke all but one of the bolts, I have never heard of that happening.

Alan

[eliminator]

I am like Alan, I can't beleive 3 of the 4 upper mounting bolts broke....

I can't beleive you could break 1 of the 4 upper mounting bolts, I don't think were talking about the same think here. I think it was the four bolts , 2 on each side that go into the side of the differential that are normally safety wired. The originals were grade 5 and tapered, the upgrades are grade 8 with a tapered sleeve. And the reason these original bolts broke was because the lower plate that most people have to tie both sides to the differential was not in place.

[RJacobsen]

Who was the member that broke all but one of the bolts, I have never heard of that happening.

Alan

Here's the thread http://www.uniquecobra.com/forums/sh...t=broken+bolts
Look at the photo in post # 18

Alan, in post #20 he indicates that this was not an installation done by you guys and it is apparent that the wrong bolts were used, but it does indicate that alot of stress can be applied to that area.

[eliminator]

Rod,

The guy used the wrong bolts, with that taper I can see how they broke. The taper is what caused them to loosen up. Plus that bolt is no more than a common Grade 5 if that. And the differntial to the frame was loose and all the load positive and negative created under aceleration and deceleration caused the bolt failure. So "alot of stress" can be easily handled with the proper bolts, hex head, grade 8's with a hardned flat washer, and the proper torque.