i was wondering if anyone new the reason why GM put the torque arm that goes from the differential to the tailshaft housing on the camaros and firebirds, and if theres advantages or disadvantages to having it?

 

Probably just because it was a relatively convenient place, and it wouldn't transmit as much noise to the body.

 

Were you just asking why the torque arm is bolted there, or why it exists at all?

 

Sounds to me like he's asking its exists at all

 

If you want to know why it exists at all, it's the only thing that keeps the rear end from turning instead of the rear wheels.

 

it prevents axel wrap . keeping rear axel , drive shaft , transmisson all in line . sort of like traction bars for the entire rear end . do not try to drive your car with out one . if you have to feather foot it till you get it back in . aftermarket front mounts are a good idea .

 

the disadvantage is they tear trans mounts up.....

It is part of the suspension system, and as others have stated, it is required. The system works very well when the proper aftermarket components.

 

Heck I think it works well stock. Compare the torque arm system to bad riding and hopping leaf springs like my 2nd gen has!! My 3rd gen rides like a dream in comparison.

 

is there a way to beef up your stock torque arm by weldind a tube to it or something. rather than having to spend 500 on an aftermarket one.

 

You could do that, but I wouldn't bother. By the time you have enough money into your engine to the point that the stock torque arm is actually (like for real!) FLEXING, and becoming a weak point in the rear suspension, you'll have 600+HP, and a $400 torque arm won't seem like a lot of cash.
For now, you can just toss in a $20 poly front clamp bushing, and poly tranny mount and call 'er good.

 

It was kinda of advanced for it's day. Compare a stock WS6/Z28/IROC rear suspension to stock Mustang and it's like night and day. I knew someone who spent $2K modifying a Mustang and it still didn't feel as good as a stock WS6. Converting to torque arm is now a common mod the Ford guys do.

Essentially, the torque arm lets the rear tires move around to follow bumps, but keeps them pointed forward better (good) than the stock quad shock Ford design which allows the rear wheels to steer the car (bad).

 

In some factory GM build ups, they take two torque arms and weld them together (double thickness). Also, aren't L69/TPI arms better (totally solid) from regular V6/V8 arms (weight saving holes) ?

When you start running higher power, the issue is where it attaches to the body and how long the torque arm is. Do a search on "instant center". There's some really good posts about suspension tuning changes that can be done by playing around with the length of the torque arm.

 

Just a cumlative response to responses. I too agree that the 3rd and 4th gen susension is hard to beat. Even Buick used a TA on the GNX to get better traction. The TA is kinda like having upper control arms but it has benefits of being tied snugly to the pinion area for strength and proved to be effective than any other possible setup given the room. I also agree that the trans mount was intended for cost reasons on top of isolating vibrations. Personallly I like the Spohn-type of TA that mounts it to the crossmember, rather than the tunnel mount. The shorter tunnel mount might improve a little on tranfer of torque and some on weight as well. But like a 'lift-bar' the torque transmitted to the fronr frame rails (stiffer mounting point) might help the overall launch and feel. It could IMO help the front frame rail flexing out. My theory : When the motor torques up off throttle it twist to the side. Pulling up on the K-member on one side and pushing down on the other. The K-member is bolted to the sub frame rails anf the motion is transferred. The torque arm front is being pushed upwards by the centrifugal force of the axle and thus the crossmember at the rear of the front sub frame rails. Being direct the front frame rails are having a negative force opposite of the motors force. Of course subframe connectors are good to have also to disperse the energy of those forces over a larger area and create a stiffer frame all togehter.