[Lowell W]

In recent threads on CC concerning driveshaft loops, there seemed to be unanimous agreement that a means of restraining the driveshaft in the event of a broken U-joint is an essential safety feature; also that the smaller the area the broken driveshaft has to move around in, the better.

Several suggestions were made: A) that a single loop is sufficient; B) that a loop at each end of the driveshaft may be required for adequate protection; C) that a centrally located ring, slightly larger in ID than the diameter of the drivshaft, may be an ideal, and simpler, solution; and D) that some kind of a shield over each U-joint may also be necessary, or at least desirable.

The central ring arrangement would be the simplest to design and build, especially for cars with IRS. If that would provide adequate protection; great! I did fabricate a front and rear loop system with 1/4" steel shields over the U-joints which certainly is strong enough, but now that I look at it on the bench, it looks way too heavy and clunky. Actually it looks like it belongs on a tractor, not a Cobra.

Before proceeding further with design and fabrication of a driveshaft restraint device/system for my car, I decided it would be a good idea to see whether anyone has had any experience with a U-joint coming apart. Assuming the driveshaft itself is restrained with some kind of safety loop, how much force is imparted to the U-joint pieces or yokes? Enough to send them through the tunnel? Enough to warrant the use of a shield over the U-joints? If so, how heavy is heavy enough? Anything else I'm missing that I need to consider?

Thanks,

Lowell