Driveshaft Loop - How to fabricate?

***R-N-R*** · 03-22-2006, 08:57 PM

Can anybody offer up a good description of fabricating drive shaft loops for drag racing?

***Graphic Man*** · 03-24-2006, 02:04 PM

Bill, That easy to fab up.!!

***R-N-R*** · 03-24-2006, 08:06 PM

Cool, what do you have in mind?

***R-N-R*** · 04-01-2006, 05:33 PM

Anybody care to offer up an idea on this?

04-01-2006, 06:13 PM

I dont know the rules at all and have never been to a track to see a driveline loop but my understanding is the loop has to contain the driveshaft if it were to break loose .............If I could see a pic of one I can build it for ya Bill

***R-N-R*** · 04-01-2006, 06:50 PM

I might have to take you up on that Kevin!

DHRA Rules state:

Quote:

In place of a cross member, in the vicinity of the front universal joint, all vehicles running 11.99 or quicker must have a retainer loop with 360 degrees of enclosure, 1/4 inch minimum thickness and two inches wide, or 7/8 inch by 0.065 inch welded steel tubing, securely mounted and located within six inches of the front universal joint to support the drive shaft in the event of U-joint failure.

I won't be getting under 11.99 with this truck, but I have also read that NHRA rules state:

Quote:

Drive shaft loops on 13.99 second and faster with slicks, 13.00 on street tires.

So I am checking just in case. I don't quite understand the "In place of cross member..." thing???

The only ones I have seen so far are made for pulling trucks. they look like extreme overkill for what I am doing, and they look like they would weigh too much as well. Unfortunately I have not seen any pics of how they tie into the frame, except for BigBadDodge which is a serious pulling truck.

04-01-2006, 07:17 PM

Man that is a serious driveline loop and looks heavy too

I bet if ya look around at the races you could get some good pics

***trik396*** · 04-02-2006, 11:14 PM

Within six inches of the front u-joint... this is the same rule for NHRA. I had a driveshaft loop I installed on my Chevelle the same way. For our trucks, you'd have to fab up a crossmember to hold the loop in place around the driveshaft. Pretty easy to do, just hard to describe with words. You can probably buy the loop from Jegs or Summit and fab up the mount to hold it to your custom crossmember.

diesel junkie · 04-03-2006, 12:54 AM

hey speakin of buildin stuff under the truck...how hard would it b to make som traction bars?

**IC-Smoke** · 04-03-2006, 01:00 AM

Bill, Look at "BigBadDodge"'s photos on TDR, hes got pics of his driveshaft loop setup. even on his webpage he has photos. If you get me some dimensions/ blueprints I can have a local fab shop build a pair

Ill be needing one as well (plus front driveshaft) R&D fabrication is cheap so no big spending

Diesel junkie- just buy a set its about the same price and alot easier!!! trust me I know. I built mine and they work great but If i was to do it again I would buy a set that is pre-fab!!

Ian

04-03-2006, 03:50 AM

You can use Oil Well Casing Also.

DM

***R-N-R*** · 04-03-2006, 06:58 AM

Oil Well Casing??

I saw BBDs, top notch job there, but overkill (weight) for my needs.

Summit had some good pics, but the products look too lightweight for our trucks.

However it appears that an oval or round loop with what amounts to "L" bar welded to it extending out to the frame for bolt (preferrable) or weld on attachment will work. I expect the that the crossmember pieces will have to be pretty hefty to handle the span. I'll have to crawl under there and get some measurements.

I will upload the pics from Summit after work today.