otofmyway6

I am getting ready to install a set of 5pt harnesses in my c5z. I have a harness bar for the shoulder belts. Im installing Corbeau A4's with sub belt holes with Corbeau brackets and sliders. I just don't really know how to install the lap belts. I am wondering how most people do it. I know of the lap belt bars, etc, but the engineer in me is concerned with adding the stress to the seat bolts. a 3 pt has the stress of the seat with 1 pt of the belt on the bolts. a 5 point would have the sub belt and both lap belts on these bolts. i'm wondering if there is anywhere to mount an eyebolt somewhere by the factory 3pt mount or adding one to the corbeau bracket? If you guys feel the bars are the best way to do it, then thats the way i'll go about this. Just curious as to your guys' solutions. Thanks!

RDnomorecobra

I hear what you're saying. I have Arizen seats and brackets and the lap and sub belts all attach to points on the brackets which in turn are bolted to the floor via the 4 stock bolts. If you asked someone that builds real race cars I think they'd say that's an example of what not to do. I think it's a matter of finding where on the frame under the car you can add bolts. Probably would involve welding additional steel under there as I don't think there's any in a good location to add mount points for lap and sub belts. I'd call a race shop like Phoenix and ask them, and then tell us all what they said.

sperkins

You should be more worried about using sliders.

redtopz

Is this only for auto-x? Or will you be going to hpde events also? For auto-x, I personally would not worry about it. For racing at the track, I would (and did) move my lap belt anchors from the seat rail to welded anchors on the car.

otofmyway6

You should be more worried about using sliders.


that sir, is a good point. however, even factory sliders are tested such that the seat wont fly off the bracket and the small teeth won't let loose. I've done all i can in that department with double locking sliders. ultimately, in a head on collision, the driver (or passenger), the seat, bracket, both lap belts, sub belt would put the rear seat bolts into tension. I know everything is overengineered, but i still am curious as to how professionals are mounting lap belts. My guess is adding a flat steel plate to the underside and top side to create a small sandwich with an eyebolt? or using some sort of attachment to the factory seat belt location?

otofmyway6

Is this only for auto-x? Or will you be going to hpde events also? For auto-x, I personally would not worry about it. For racing at the track, I would (and did) move my lap belt anchors from the seat rail to welded anchors on the car.

redtopz, i plan on doing HPDE as well, but in any situation would like to make sure im as safe as I should be, especialyl with things like seat belts. Hitting a light pole at 70mph isnt any better than hitting a wall at 70mph. I will definitely see about where and how to weld anchors to the car. do you have any pictures by any chance?

Bill Dearborn

First thing you are looking at the difference between the stock setup which has one belt mounted to the seat rail and thus to the floor stud with the other mounted to the frame Vs a setup with both belts mounted to the seat rails and thus both rear studs. This is the difference of one bolt. Sub belts don't come into play as your weight is the only other variable. I seriously doubt GM used a different inside stud or mounting method for that stud Vs the outer stud so the outer stud has the same strength as the inside stud. If you look at how the stock belt pulls on the seat frame you can see that force is translated directly to the inside stud. If the inside stud can hold half your weight the outer one can hold the other half of your weight.

If you had a C6 you would know both ends of the stock belt bolt to the seat frame and thus to the rear floor studs. I don't know the difference between the C5/C6 in this area but I believe there is enough strength in the C5 rear seat studs to mount both ends of the lap belt to them or the rail.

The advantage to using the stock mounting locations is they have been tested and proven in crash tests. Without a roll cage in the car there is no way for you to know whether or not any mounting method you come up with is as good as the stock setup.

Bill