Something I've been having trouble getting a straight answer on is where is the best place to attach the harness. I've heard some say far away to allow a little "stretch" on impact. And other more reputable sources say as close as possible to the seat (the harness bar) because there is a reduced chance of deformation (less likely to have a change in the tension of the harness) on impact.

Does Any one know of any sanctioning body rules that would apply to this?

 

The NHRA rules are pretty good about telling you where. Which point(s) are you asking about?

 

The safest place and method of attaching the shoulder belts.

 

This is from simpson's website

 

I understand about the angles and related compression forces of the shoulder belts, but what about the mounting location/style? Is it better to bolt them to original belt holes in the rear seats. I've welded in a rear tower bar, should I loop the belt around those? Or is a harness bar directly behind the driver seat the best location, and if so what mounting style?

 

The G2 harness bar mounts it on the rear shocks, I wish they still made them though

 

LG harness bar mounts to the rear seat belt attaching points, not the shocks.

 

Id say as close to seat as possible, that way you will limit the stretch in an impact.

 

That appears to be going to the rear upper seat belt mounts. The rear shock mounts are just a hole in the body where the shock comes thru. I don't think you want your harness bar mounted to those.

I would say having the proper height for the bar so that the harness is at the correct angle is more important than the distance. I'm sure you don't want it too far away, but harnesses come pretty long (at least my RCI's did), so I'm sure any reasonable distance is OK.

 

Presuming Angle, seat position, and cage construction are percect: How and Where is the best method/point of attachment?

Is there any advantage to be gained with bolt-in verses wrap-around or vise versa?

Any one have any links or quotes from FIA or sanctioning body rule books that say closer/further attachement points are safer?

 

Yeah my Sparcos came long too. Isn't there supposed to be a certain length they need to be to stretch properly, in the event of a crash?

 

Mine are looped around the horizontal cross bar. As long as they are below the shoulder (3"?) they are legal. I have seen poeple weld tabs & loops onto the bar to keep them in place. That is my plan eventually. But it's not required.

 

I prefer the wrap and buckle as opposed to bolt to the buckle.

The webbed material is not stressed with such a sharp return when looped around the bar. When grossly stressed, the buckle can act almost knife-like. I've seen buckled webbing fray where they loop through the eye-let.

 

It's actually determined by a max angle, not inches below shoulder height. Horizontal to the top of the shoulder is ideal, while any mounting position below that (especially at an angle of more than 30 degrees) you run serious risk of spinal compression in a front impact.

 

Buddy of mine sent me this when I was considering getting a 6-pt put in my car. Hope it helps

 

From the Simpson racing website ...

http://www.simpsonraceproducts.com/images/big_up6pt.gif

 

Mine's shipping here from a user. Should be here next week. That picture shows the best way. Harness bar bolting into rear s/b brackets and either bolt the harnesses into the bar or give it the wrap-around. I'm partial to the wrap-around myself, and not ashamed to say it. HAHA. Some harness bars (Sparco) don't even have bolt holes for the belts, so you have no option but to wrap around.

 

ok we have talked about the shoulder straps.. but where are you guys mounting your side straps to? are you using the stock seat belt holes? i currently am right now because i have bolt in harness's, but my new belts are clip in.. and i need to use Eyebolt's. i have not yet found an eye bolt with the same threading as the stock seat belt holes...

 

And you probably won't.

If you look under the car, you will notice the factory seat belt backing plate is oval shaped. You can drill through this plate next to the factory hole and probably be good to go.

The outside is a little tougher.

You drill through the floor pan and use big washers or a welded in backing plate or you can cut a hole beneath the stock mounting hole, shove in the eye bolt and bolt it down with the hole you cut big enough to get a wrench on the nut. Then, pop rivet a section of metal over the hole, sealing it with RTV.

Make sure you pin or safety wire those clip in attaching points.

 

Instead of drilling through the floor, what if you found an eyebolt in a slightly smaller dia./thread pattern, put it through the factory threaded hole, and put a nut on it on the underside of the car.
Would that work?