harrisonrick

anyone ever thought that the torque tube is destined to fail? since the actual drive shaft is hardened steel, it is basically held into the clutch end and trans end that you could do away with the tube and bearings? I realize it spins @ 6000 rpms, however if it was for a track car or summer driver couldn't this work?
you could fashion a cover for the clutch end out of aluminum or steel and bolt it in place in the bolt holes available, with a 2 inch hole for the shaft to come out of and do the same for the trans end...or am I deleriously tired and should go to bed?

just thinking out loud.

V2Rocket

I don't see why not...

you'd need to find a new place to mount your shifter though.

924Superwagen

Yes, it is hardened steel, but it would be unsupported over a fairly large span... same principle as having the bearings fail in the torque tube. I think you'd go nuts from the vibration. Also, the torque tube is an integral part of the driveline structure, preventing the engine and transmission from twisting. If you were to remove it, it would definitely add stresses to components that are already fragile (ring & pinion come to mind)

Funn944

Nighty-night........

KuHL 951

You have to remember that the torque tube is an integral part of the entire drive train design. The Porsche 944 design as well as Miata's Power Frame is what makes the cars feel so connected. It imparts rigidity and a rock solid connection to the motor. Most rear wheel drive cars treat the motor and trans as two elements of the drive train, on the 944 it's one. An open drive line is not coupled mechanically or structurally to the chassis. You would have to fabricate a pair of u-joints and use a tubular driveline like most RWD cars. You would gain nothing in weight reduction, increase vibration, and probably increase torsional flexing of the transaxle. Drive train power loss would certainly increase as well. It really is a great design for sports cars and you really can't say it's "designed to fail" anymore than other components on the car. In truth the TT has a good history of longevity on these cars both stock and in higher powered turbos.

V2Rocket

These guys prove a good point. There's probably a reason you never see the track guyssaying "TT delete".

If you want to lose weight on your car take out the wiring there's about 50 lbs of it.

harrisonrick

maybe it was the rye talking....

art

I think the driveshaft being small dia helps to reduce its moment of inertia. If you were to replace it with somthing that was strong enough to be unsupported, it would be larger and have more rotational moment of inertia and thus hurt shifting since all of that mass needs to change speed when you shift. The comments about the torque tube being part of the trans and engine mounting are probably even more appropriate. People have made aluminum torque tubes...

If you are taliking just about failure, these bearings actually have a pretty easy life, so they will last a long time and are not too difficult to replace (once you have the tube out!).

I've thought about how cool it would be to use a 944/924 trans in a project car such as british roadsters where you would build a torque tube and use the trans with an IRS setup which would help weight distribution and give better gearing.

Van

With a driveshaft/torque tube delete, you could also save weight by removing the engine and transmission, since they won't be doing you any good without the torque tube...

Then you could use the car for soap box derby, or, better yet, mount a little sail on the top and breeze around in parking lots! You wouldn't need a life jacket.

As the others have mentioned, deleting the tube isn't an option, because the engine is only supported by two mounts (3 points define a plane) and the transaxle hangs like a coat hanger. By the time you reenforce the body, make extra mounts for everything and install universal joints, you'll probably add all the weight you just took out.

I do seem to recall something about someone making an aluminum torque tube. Anyone remember that?

Dan Shea

psshh if you're going to do aluminum, why not be a baller and get carbon fiber. now that would be neat to design and make functional.

KuHL 951

Talk to Dave951M, he builds them or used to. He actually had one for sale about 6 months ago.

https://rennlist.com/forums/showthre...um+torque+tube