Driveshaft loop location.

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Mopower71

Speed Demon
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What is the NHRA spec for the location of the driveshaft loop?
If I remember it is suppose to be 6" behind the front u-joint.
I would like to move mine back a bit, but want to make sure it will pass tech.
 
It says 6" max behind the front u-joint.
The further back the loop is placed, the more dangerous the front part becomes. The back end whipping around is behind you and the driveshaft will want to exit towards the back. The front part whipping around is usually right next to you and is most important to "contain". Moving it forward, to less than 6", is safer. There is less room for the tube to bend at the front, especially when the front joint breaks and the rear is still attached while going down the track.
 
Thanks Myron,
I'll see where I can squeeze it in. The one that was there previously was at 6" but connected to the frame rail connectors. With the new exhaust going on there was no room for it, so I am going to use a universal one. That one just doesn't sit into the driveshaft tunnel very well, as when it is touching the tunnel the mounting plates are around 3/4" from the floor, and it is right where the seat bolts come through the floor.
 
6" max from the center of the front u-joint..1/4" minimum thickness..2" wide,or 7/8"welded steel tubing..
 
Has anyone ever seen a tech guy get under your car and measure where the drive shaft loop is??? I just cant see that happening.
 
Has anyone ever seen a tech guy get under your car and measure where the drive shaft loop is??? I just cant see that happening.


I've had it done a few times at new england dragway..kind of like it they check everything,unlike some other tracks i race at..
 
I was going to put a universal on my car but when I got it out of the box and under the car.... back in the box it went. There is no room for it! I don't drag race anyways. lol
 
That's the problem with this universal one.
I have shortened the upright on the L bracket. The hoop part rests against the tunnel and the brackets are around 3/4" from the floor. I'm not sure I can bend the 1/4" thick steel. Will have to bend the 90deg bend tighter to like 45deg, then put a bend back down so it will hit the floor properly.
 
Lakewood universal that i pulled off my Roadrunner. seemed to fit better than expected.

swinger 276.jpg
 
That's the problem with this universal one.
I have shortened the upright on the L bracket. The hoop part rests against the tunnel and the brackets are around 3/4" from the floor. I'm not sure I can bend the 1/4" thick steel. Will have to bend the 90deg bend tighter to like 45deg, then put a bend back down so it will hit the floor properly.

I used a universal and drilled an extra hole on each side so I could bring the top loop down which allowed the brackets to be a lot closer to the floor.
 
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