Mount for five point crotch belt

[ukchris]

My car has six point harnesses, for one reason or another I now have a brand new set of five point harnesses so… is there a better/worse way to mount the crotch strap? The six-point ones were bolted through the supports that run on the underside of the floor, for a center mount how much reinforcement is necessary? Obviously it’s fairly easy to drill through the floor but would it be better to run a piece across the other two sturdier mounts? How about bolting a bar running fore/aft on the underside? What would you recommend to anchor a center cross strap?

[kayentaskier]

Hi Chris,

Not sure if you have Caterham branded crotch strap, but this blog may be helpful to you:

https://www.caterham7diaries.com/post/crutch-strap-install

Regards,

Jim

[ukchris]

Thank you - isn’t that essentially six point though? I have a single crotch strap that, as I understand it, needs to be secured forward of where it comes through the seat? I read 6 points behind, five in front. 
 

simple plan would be to drill a hole in the floor and bolt it in but not sure if that’s strong enough. I could also but a bar on the underside, bolted in and bolt through it (essentially 3 bolts holding it) and trust the bar isn’t going to pull through. 

[CarlB]

There are lots of places on the web that tell you how to mount harnesses. You are correct the single crotch belt is mounted forward and the double one is mounted to the rear. I have not seen any place that says how the belt should be secured. The SCCA is not very specific. They allow belts to be attached to the floor if a large diameter washer or backing is used. My submarine belts are mounted with 1/8 inch aluminum plates top and bottom that are 4 inches long and 3 inches wide, as well as big steel bumper washers.   

[ukchris]

18 minutes ago, CarlB said:

There are lots of places on the web that tell you how to mount harnesses. You are correct the single crotch belt is mounted forward and the double one is mounted to the rear. I have not seen any place that says how the belt should be secured. The SCCA is not very specific. They allow belts to be attached to the floor if a large diameter washer or backing is used. My submarine belts are mounted with 1/8 inch aluminum plates top and bottom that are 4 inches long and 3 inches wide, as well as big steel bumper washers.   

Thank you, I have a 6” steel bar that is pre-drilled with four holes, I am thinking I’d drill the floor and bolt it to the floor with two bolts then run a third through it for the belt. I suppose I could mount it fore/aft or across the floor, not sure if one would be stronger than the other or not, I don’t plan on racing, it’s more about getting the belts installed as I may be selling soon.