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6spdmalibu
07-24-2009, 11:56 PM
Am contemplating fabricating a decoupled torque arm setup for my '81 Malibu.

A little about the rear suspension of the project.
Currently running Global West lower control arms, Del a lum bushing axle side and spherical bearings frame side. Stock rubber bushings and upper arms. Both tied together with Edelbrock braces. No sway bar. Eibach springs, and Edelbrock IAS shocks holding an 8.5" 3.42 posi rear end. With camaro disc brakes.

Now, I've driven this rear set up for 7 years. And have found the limitations of this setup, well.......it's time for an upgrade!

My idea is to fabricate a cross member just behind foot wells of the rear passengers.Where the torque arm pad pushes up and upper link mounts to. That will be braced back to the pinion stopper area for strength and rigidity. The frame area around the pinion stopper will also have to be notched for the brake arm. Will be fabricating a torque arm mount that is attached to the diff cover area using studs. If only I could find a GNX cover for a decent price. That would make the whole job just a little easier. Will also be fabricating new mounts for the frame and axle side. The torque arm will be mounted to the passenger side to help combat torque. Which brings me to a few questions.
Should I use the stock lower converging arm set up, or go parallel links? Will one work better with the decoupled torque arm setup? Will roll under steer be achieved with either? Are the stock length arms adequate length?
Also still not sure whether to use a panhard bar, or a watts with this set up.

Yeah, I realize that I could just throw some money at a few bolt ons to gain a little more performance. But it'll still be a bind laden, late 70's designed suspension. Thought about a satchell link rear suspension also. But the length of the upper arms would be to short for what the design calls for. As I'm trying to get a larger "sweet spot" in the articulation of the suspension.

Any comments, questions and answers would be appreciated.
Thanks, Jerry.

6spdmalibu
07-25-2009, 09:24 AM
If anyone could point me to some literature on decoupled torque arm setups would also be appreciated.

Jerry

jackfrost
07-27-2009, 09:42 AM
you might want to check out the SC&C watt's link. it's supposed to solve a lot of problems and won't be nearly as complicated. even if you decide after you still want a torque arm, now you've got your watts.

6spdmalibu
07-28-2009, 10:19 PM
I took a look at the watts link by sc&c. Clever design. With the ability for roll height adjustment and end link location adjustments. Though am wondering how much weight is added by its design to the unsprung weight of the axle? Most of the watts links I've seen have the center bolt attach to the differential instead of the support brace. Would like to know if there is some kind of benefit to the sc&c design over the latter?

Bad Bird
07-29-2009, 04:26 AM
Sure. Less unsprung weight and a constant roll couple.

79MALIBU
07-30-2009, 03:42 PM
I have been running this upgrade all summer on my 79 malibu, street/autocross/drag car, emphasis on Autocross. This is by far my favorite upgrade to date! Espicially if you allready have joints installed in the rear. Its simple, when i go to tracks with different levels of availible track, I adjust the watts, and everthing is great again. If i need more over-steer i raise the roll-center, If i need less I lower it.

The addition unsprung wieght is negligable. The axles clamps are steal, with a large bolt. I would guess they add, maybe 10lbs tops. the rest of the unit is supported by the frame.

If i could go to any setup possible for the rear as far as links go, i would go to a top link with a push-pull bar. see http://www.stockcarproducts.com/rearsusp.htm

But this would take some serious FAB! to do correctly.

There are flaws in a panhard design that cannot be avoided, and I would never run one.

Just my opinoin and experiance, bottom line, I love the watts link!

6spdmalibu
08-02-2009, 07:24 PM
Well, I'm sold on the watts link! One down.

ITLBTU
08-03-2009, 01:29 PM
If anyone could point me to some literature on decoupled torque arm setups would also be appreciated.

Jerry

Here's a link to a company that makes a de-coupled torque are for a 3rd gen Camaro. I was thining about modifying it for my 69 Camaro...

http://www.unbalancedengineering.com/Camaro/TA/

6spdmalibu
08-03-2009, 04:57 PM
Thanks Greg. Also found this site:http://www.f-bodysport.com/decouple_torque_arm.htm


Jerry