Please folks, use caution when it comes to shoulder harnesses. I beg to differ with Bob on this topic. Five point harness assemblies (particularly the shoulder harness) absolutely must not be mounted higher than the shoulder. It’s an invitation for disaster or worse. I’ll be blunt: You can kill yourself with that approach.
As some of you know, I’ve been involved in racing for quite some time – and all of it with the NHRA (National Hot Rod Association). I’m also an employee of the NHRA. What you might not know is that we have one of the most comprehensive sets of safety regulations in all of motorsports. We also have an admirable record of keeping people alive in race cars. Seat belt and harness mounting is definitely part of the regulations. While a three point harness, as you will find in almost every passenger car on the planet is designed to function with a high shoulder harness mounting point, that same location can (and regularly will) prove fatal when applied to a race-style dual mount shoulder harness. Here are two excerpts from the NHRA Rule Book:
SECTION 10:5 DRIVER RESTRAINT SYSTEMS
"A quick-release, 3-inch shoulder harness meeting SFI Spec 16-1 is mandatory in all cars in competition required by the rules to have a roll bar or a roll cage (Permitted in all other classes). Driver restraint system must be clearly labeled as meeting SFI Spec 16.1 and dated by manufacturer. System must be updated at two-year intervals from date of manufacture. All seat belt and shoulder harness installations must be originally designed to be used with each other and produced by the same manufacturer. For harness installation, see illustration. Cars using OEM or OEM-type seat may route crotch strap in front of seat instead of through seat. Only those units that release all five attachment points in one motion are permitted. When arm restraints are worn with a restraint system that utilizes a "latch lever", a protective cover must be installed to prevent arm restraint from accidentally releasing the latch lever. Protective cover not required if system utilizes "duck-bill" latch hardware. All harness sections must be mounted to the frame, cross member, or reinforced mounting, and installed to limit driver's body travel both upward and forward. Seat belts may not be wrapped around lower frame rails. Under no circumstances are bolts inserted through bolt webbing permitted for mounting. Check manufacturer's instructions."
SECTION 10:11 SEAT BELTS
"All cars not required by Class Requirements to use SFI 16.1 driver restraint systems must be equipped with an accepted quick release-type driver seat belt (All cars in competition requiring a roll bar or a roll cage, or as outlined by Class Requirements, require a five-point, 3-inch wide SFI 16.1 restraint system. See 10:5 DRIVER RESTRAINT SYSTEM). Belts must be securely fastened to the frame, cross member or reinforced mounting so that all fittings are in a direct line with the direction of pull. Seat belts may not be wrapped around lower frame rails or any frame rail or cross member, such that belt may be damaged in event that frame rail or cross member comes in contact with racing surface. Steel castings of the type recommended by the FAA or U-bolt-type mounts are permitted. If used for installation, flat steel plates must be a minimum of 1/4-inch thickness and have rounded edges to prevent cutting seat belts. Under no circumstances can belts be installed with bolts through webbing. In all cars with fiberglass floors, a cross member (minimum 2-inch X 2-inch X .083-inch wall thickness square tubing) must be installed between frame rails for proper driver's seat belt installation."
As you can see, harness assemblies must be used with some form of crotch strap. Otherwise you will submarine (downward) out of the belt during impact. Also, harnesses must be mounted in a location either level with the shoulders or a maximum of four inches below the shoulder. A mount that is higher than shoulder level is not acceptable.
If it works, I’ve included a GIFF that shows the accepted harness mounting arrangement. If, by chance the GIFF doesn’t show up, please feel free to contact me and I’ll gladly e-mail a copy to you.
Sincerely,
Wayne Scraba
Wayne Scraba Motorsports
Kirkham Owner & Dealer
PH: 250-658-4222
E-Mail: wcscraba@coastnet.com