NHRA Accepted Drive Shaft Safety Loops

For G-Bodies.

The NHRA requires all cars that run 13.99 or faster to have a drive shaft safety loop that meets general regulation number 2:4.

The G-body cars came from the factory with a drive shaft safety STRAP, but this strap is non compliant with NHRA general regulation number 2:4.

Here is the complete specification word for word.


On any car in which the driver sits over or in back of the rearend center section, a suitable protective shield of .120-inch (3 mm) minimum thickness steel plate must be installed for those units with universal joints securely mounted to the rearend center section and the bellhousing adapter. Where possible, couplers are recommended in place of U-joints. For straight couplers, the minimum requirement is .063-inch (1.6 mm) aluminum which must contain an inspection cover for removal and inspection of the coupler, securely mounted to the rearend center section and the bellhousing adapter, or as noted in Class Requirements. In place of a crossmember, in the vicinity of the front universal joint, all cars in competition using open driveshafts, must have a retainer loop 360-degrees of enclosure, 1/4-inch (6.35 mm) minimum thickness and 2-inches (5.1 cm) wide, or 7/8-inch (22.2 mm) x .065-inch (1.65 mm) welded steel tubing, securely mounted and located within 6-inches (15.2 cm) of the front universal joint for support of the driveshaft in event of U-joint failure. Recommended the loop be round rather than oblong to minimize loading on loop. Open drivelines passing any part of the driver's body must be completely enclosed in 1/8-inch (3.2 mm) minimum thickness steel plate, securely mounted to the frame or frame structure.

I have designed a series of driveshaft safety loops that, meet all of the specifications set forth by the NHRA, are as light as possible, bolt up to the stock strap mounting position, allow you to use up to a 5" diameter drive shaft, and are easy to install.

Installation Instructions.

It is a direct bolt in.  To install all you have to do is unbolt your old factory strap and disconnect your drive shaft at the rear U-joint.   Slide the drive shaft into the transmission a little and slide the loop on to the shaft.  Reconnect the rear U-joint and bolt the drive shaft loop in where the factory strap used to be using the longer than stock mounting bolts supplied. No cutting welding or fabrication is required.

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Rationale Behind The Design.

The reason I chose to make the loop solid is that it this way it will be as light as the NHRA will allow.  If I were to make it to where the loop was sectional or bolted to the strap there would have to be over lapping metal and four  to eight 3/8" bolts and nuts, this would result nearly ONE POUND of unnecessary steel.   With this loop you can use up to a 5" diameter drive shaft.


The FastMonte.com drive shaft loops are made from cold rolled 1018 steel.   This stuff is actually tougher than nails.

Two Models Available.

The standard model is a direct replacement to the factory strap.
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The 3" set back model sets the loop back three inches to clear a longer transmission like the ever popular 700R4, and selected manual transmissions, (T5).  This model will also work with the regular length transmissions, so if you think you might go to a longer transmission in the future this would be your best choice.
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Choices of Color.

Each loop includes longer than stock mounting bolts and finished in your choice of red, or raw unpainted steel. I use high temperature chemical resistant enamel paint.  When painting the loops I subscribe to the theory of runs instead of rust.  No one will see it after it is installed anyway, except for the tech inspector and the mechanic, neither will think less of you.


NHRA legal 0" setback loop is $45.00 in person and if they need to be shipped you pay 7$ shipping in the continental US and reasionable shipping if you are located elsewhere.

NHRA legal 3" setback loop is $55.00 in person and if they need to be shipped you pay 9$ shipping in the continental US and reasonable shipping if you are located elsewhere.

You can save on shipping by buying multiple loops.

How To Order.

Send me an E-mail at the following address. MetalMaster@fastmonte.com You will need to include, what model you want, (either the standard, or 3" setback model), the color you want, (red, or unpainted steel), and your shipping address. Please see the Terms Of Payment page for payment information.