Bob…I understand the question completely, but there is a considerable difference between the type of belt installed in a passenger car and the type commonly used in Cobras or race cars. In a typical passenger car, the belt latch is off to one side (commonly on the extreme lower right for the driver and on the extreme lower left for the passenger). In this case, the shoulder “strap” is routed diagonally across the body. Because of the 3-point arrangement, it is possible to use a high mounting location for the shoulder strap. This is not the case with a five point harness. In order to determine the correct mounting (anchor) points in the given production vehicle (passenger car, light truck, etc.), it is obviously heavily instrumented and crash tested (and likely many more times than once). As you must be aware, the mounting point location for three point belts in a passenger car application is not an arbitrary decision.

In contrast, the race lap belts commonly used are latched in the center. As a result, the shoulder harness is latched in the center, not diagonally. Because of this, you must use the appropriate harness for the belt. And when you use a proper race style shoulder harness, as shown in the NHRA illustration, it is mandatory that a crotch strap be used. If not, you will submarine out the bottom of the harness, causing severe, if not fatal injuries. You cannot use the center latch belts with a single diagonal shoulder harness.

Now, my question to you: How can you engineer a proper, tested diagonal 3-point harness assembly for use in a Cobra? Where do you suitably anchor the diagonal? We have plenty of information to go on as far as race car harnesses are concerned (SFI has done considerable research, not to mention General Motors’ in depth investigations), but in the case of a Cobra (or other kit car, street rod or modified vehicle), how do you know a single diagonal assembly is suitable or sufficient?

You’re up to bat.

Wayne Scraba
Wayne Scraba Motorsports
Kirkham Owner & Dealer