My Lakewood driveshaft loop doesn't fit due to interference with my UMI adjustable torque arm with a trans mounted bushing and the 3" steel driveshaft w/1350 u-joints.
Who's done what for a loop?

 

Minimum requirement for a loop is 2" x 1/4" flat steel or 7/8" x .065 steel tubing.

Since my car isn't anywhere close to being stock, I fabricated my own. I run a 3" steel driveshaft. I made loop from steel tubing. 1" OD and 0.120 DOM. I bent it in a loop around a mandrel. Between my SFC, I welded in another piece of tubing like a small crossmember then welded the loop to the tubing. The loop is within the required distance from the u-joint and even though it's all welded in, it still allows enough room to pull the transmission.

Look at how the aftermarket torque arms have attached a driveshaft loop directly to the crossmember. Since you don't use an aftermarket crossmember, design something to make a loop that's attached to the aftermarket torque arm.

You can always upgrade to a better torque arm that attaches to an aftermarket crossmember and gets it off the back of the transmission, that also has a loop built into it.

 

Any car that leaves the shop I had helped manage always had a tubular loop just as you described. We'd buy mandrel bends and cut them to suit.
The idea of a loop attached directly the torque arm is the one I think I'll pursue. I've seen a piece of 4" or 5" diameter pipe (like a schedule 40 with a .237" thickness) welded to a tubular arm. Looks like it worked pretty well. Seems to me there's an aftermarket version of this out there somewhere too.
As for relocating the torque arm to the crossmember, being primarily a street car, I'm concerned about the noise transfer. I've heard of some unpleasent side effects from making that change.

 

I was considering a 2" slice of 4-6" pipe when I was working on loop ideas. As long as it isn't cast, it should work just fine although it will add more weight than I wanted.

The ID needs to be big enough so that the u-joint yoke will pass through it so you can get the driveshaft out.

 

i know what you mean, I went to the spohn pro series arm and with the huge driveshaft I have and the arm it is so tight in there im going to really have to work on getting the loop to fit without any interference.

 

The schedule 40 pipe I work with is all extruded so the casting isn't an issue. It's making it work with the afftermarket torque arm that's got me to thinking. Like I said, I've seen one (welded pipe section directly to the torque arm), however I can't recall who's product it was.
It certainly is tight in there. I know I'd be far better off to relocate the mount to the crossmember so as to make a little more room. I thought I saw a crossmember style mount that received the clamshell style torque arm support rather than the rigid heim joint style connector. That would take some of the transferred road vibration out of it I'm sure.

 

I run the jegster one made for our cars. Not a problem with it and I run a nitrous ready 3" unbreakable driveshaft from dennys. Worked when I had a 700r4 and a shorty tq arm but its made to clear the stock style tq arm too.

 

Couldn't find it at Jegs. Just the Lakewood part is listed

 

Hey, just saw it in jegs again. # 550-40732

 

I just might pick that one up.
I'm working in a machine shop these days that specializes in all manner of pipe. If I can't find something suitable and weld it to my torque arm, that Jegster piece looks to be the best out there or at least when compared to the Lakewood part I have (or had).
Thanks.

 

It hugs the floor pan very tightly and it's even clearance for the tq arm. It's the one I run.

 

Version #1


Version #2

 

That's interesting.

Does that fit the spec above? (I can't tell you what it is off the top of my head) I'm at a sanctioned IHRA track and might end up in a deep tech inspection.