Seat Harnesses and roll bars

I would lookup Sports Car Club of America web page and find the Rules "GCR" , the part on safety belts.

Belts not mounted at the correct angles can injure your spine in a collision and couse more damage the a standard seatbelt.

 

Maybe so, i hadn't heard that before. When i picked the mounting point's for my belt's, i was limited on the outside belt to where it could be attached. I chose the bolt's that held the bar down because of positioning. They were exactly where they would need to be in comparison to the seat. And those bolt's went through the body into the frame. When i bolted the center belt's down, i didn't want them to just go through the floor considering the outer's were through the frame. So i used the crossmember as the mount.
In all honestly, if i was to wreck that car bad enough to seperate the body from the ch***is i have a feeling i woudn't have to worry about much of anything after the accident..i probably wouldn't survive anyway..
But you did bring up a point that i hadn't heard of before.

Tony

 

I understand and agree, but just FYI. One of the reasons is so that minor shifting of the body on the frame, or a huge dislodge in a wreck won't cut the belts or break the bolts. Obviously we're thinking a huge hollywood-off the cliff-40 roll-shrapnel crash, but the thought is that a 10mph fender bender MIGHT shift the body on it's mounts and snap the belt bolt.

 

Here's a little somthin' from Circle Track:
http://www.circletrack.com/techarticles/nascar_seatbelt_system_tech_inspection/index.html

 

Scooter, a 3 or 4 point shoulder harness system without the anti-submarine belt is much more likely to cause compression of the spine and pelvic injury in the event of a major incident. That's why the anti-submarine belt is required by the major sanctioning bodies. I know you aren't interested in compliance with racing rules but, they do have ideas that are nice to follow sometimes.

Don't let the notion that you're not racing on the strip, fool you. You're in much more danger while driving out on the street than on the strip, so a better system, even if it costs more, may be worth it.

Hank

 

This is true! Chances are an accident that would occur on the street would also involve another vehicle and unpredictable impacts.

This is a good discussion!

On another note, Hank... MAN I wished I lived closer to your shop! You are the tube bending MASTER!!!! LOL!

 

Maybe tuck a hoop all the way in the back corners and up high. Then run forward tubes over the rear side windows up to the doorjamb. Then reinforce the doorjamb with whatever thick wall 1x2 or such that could slide in there, or maybe 1/8" plate on 3 sides. Would stiffen the rear of the car for sure.

Since this isn't NHRA, there's no rule stating your "roll bar" can't be rectangular tubing. Yeah, round is strongest, but something is better than nothing, and rectangular is often easier to hide with upholstery.

 

Check out Schroth for some interesting stuff on harnesses. Yes, it is sports/race car stuff but there is a lot of good info. I had a set in a street car and a set in a formula car that I ran previous to my conversion to the traditional side and they were great. For 4-point mount street car stuff, they have a slider in the shoulder harness called the ASM system to prevent submarining without the crotch straps (yes, plural as in racing we were moving away from 5-point to 6-point but at the moment I do not remember why - maybe groin/family jewel damage?). Their site is www.schroth.com
http://www.schroth.com/installation-instructions/en/index.html has a lot of interesting stuff.

http://www.hmsmotorsport.com/store/schroth sells their stuff in the US and what is cool about their site is the pictures and instructions on every set-up.

 

WOW! Some nice looking products there! Big money and pretty TECH stuff, but WOW! The "Auto Control" series has the retractors and it looks like that ASM you're talking about. Interesting stuff for sure. Good mounting info on that Schroth site also. Thanks for the info!

Shifty... was thinking like you mentioned actually. Maybe even a combination of rectangular and tubular. I definitely agree that tubular would be the strongest though.

 

32 roll bar


The 32 has a four point roll bar made of 2 1/2" x .120 wall DOM tubing.

Bending the larger size required the tubing to be sent to an oil field tubing bending outfit.

All four points are welded to 1/4" flanges with two 1/2" grade eight bolts per flange.
The angled braces go as far back on the frame as is reasonable.
IE: before it turns to go down again so as to get a fairly straight angle for the tubing flange.

The roll bar mounts are 2" OD cold rolled with a step machined in as well as 1/2-20 threads.
The step is 1/8" as is the frame.
The sides of the round weld bung have to be trimmed 1/8" per side and round over a very small amount so they'll fit inside the boxed 1/8" frame rails.

The idea is, the threaded weld bung won't pull through the hole even if the weld failed.

I did talk to an NHRA tech about doing a cage this way.
He went to a higher authority and they said they wanted the cage welded directly to the frame rail.
I think the welded, stepped threaded bung is a stronger setup than welding a 1/8" wall thickness tube directly to a 1/8" frame rail.

Along those same lines, they allow a bolted in with large flange on the uni-bodies.

In any event we won't know until some destructive pull tests are done and the two methods are compared.

Fww, the roll bar in the pic fits under the 32's top, the interior rear view mirror is usable, none of the view is blocked and the top folds over the roll bar.

Another shot showing my 5'6" daughter and how she fits in the car.

 

Thanks for sharing C9! I figured you would have something good to add for us! Nice setup!

 

You're welcome Mr. Scooter.

One thing to keep in mind about roll bars like the 32 has is that they did a fair job of protecting the driver in a rollover at the strip back in the day.

Absolutely no doubt that today's roll cage requirements etc. are much better and drivers walk away from some scary crashes.

In my case, I wanted somewhere to hide in case the car ever did go over and copying the old style - including the large OD tubing - looked like a reasonable compromise between comfort, ingress & egress and safety.

I run a lot of errands with the 32 - any ol reason to take a spin in it, right? - and having to clamber in and over a cage doesn't really cut it on the street.

Besides, roll bars are trad....

 

These two paragraphs are exactly the type of thinking I'm having. I really don't want this car to be any more of a pain in the *** to get in and out of than it's already going to be. Chopped and channeled and low to the ground proposes it's own body contorting entrance. Adding side bars and things to look out for overhead would turn it into a jungle gym and would get annoying on a daily driven car. I won't even go into the *****ing and moaning of certain p***engers that would otherwise enjoy going to a car show or take a road trip but won't because of the added pain in the *** of getting in and out. The car still needs to be enjoyable and practical (if that word can even be used at all for what we do).

 

The 32's ingress and egress maneuvers are different due to whether the top is on or off.

Regardless, no contortionary - izzat a word? - changes required once the roll bar goes in top on or off.


A couple pics of the top folding over the roll bar.

 

Hey! That's pretty slick! Like it!

 

So I know there are a few of you running harnesses in your cars. Still haven't really heard from the guys running them in their rods and what they think of them (pros and cons).

 

Only thing I can add to your last comments, I've run a few coupes and sedans with just a lap belt.

Ran little brothers Henry J @ 10.26, full harness etc.

And ran a flathead fuel dragster with full harness.

Not to mention running the 32 a few weeks back.


Anyhoo . . . the coupe and sedan felt, for lack of a better word, normal, cuz that was what I was used to.
Sedan was my first car and I had lap belts in it about a week after I got it summer of 1956.

Little brothers HJ felt kinda normal as well since I'd tried it on several times during a couple of its build ups and ran it with the stock frame & 6 or 8 point roll bar into the 11's.

The little fueler - a slow one it was, but fun . . . my pal never did get it jetted rich enough to run well - seemed kinda normal too.
Really weird part about it, once you're strapped in and launch it's kinda like watching a movie.

The roadster was a little weird.
Lap belts only.
Feels kinda open and exposed when running the dragstrip sans top.
Probably all the Arizona sunshine floatin' in at speed.

Some of the sporty car accessory Y harnesses look like a good way to go.

After getting a set of seat belts out of a wrecked Ranger pickup to replace the torn & frayed one in my Ranger it doesn't look too difficult to set up a retractor and slide on the 32's roll bar and have some stock three pointers which would work well on the street.

Fwiw, the 32's roll bar chrome plating only goes down a little way below the rear ****pit rail.
Done that way so I could do some welding if necessary later on and it saved a few bucks in the chroming process.

 

4-point harnesses are kind of a pain for daily use, but I prefer them to lap belts. Make sure you mount your shoulder harnesses some distance above your shoulders to lessen the risk of spine compression.

As far as roll bars go, just be sure that your helmetless head will at no point come in contact with the bar. Even with foam padding, a hard hit to the noggin' will turn you into a vegetable if not kill you.

 

Do you have an OEM shoulder belt or harnesses in your daily?? I know you have some trick seats and a cage, but couldn't remember what you had in the way of belts.