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Harness Bar for Gremlin

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WesternRed View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote WesternRed Quote  Post ReplyReply Direct Link To This Post Topic: Harness Bar for Gremlin
    Posted: Feb/13/2021 at 2:04am
Is anybody running just a stand alone harness bar in a Gremlin or similar, any pictures of how it's mounted? Seems like a pretty simple concept to me.

Basically the local regs require me to run a 4 point harness, but I'm not going fast enough to need a cage at this stage. I don't think I can just bolt the shoulder straps into the floor and meet the specified belt angle requirements as they will be on too steep an angle even if I use the highest possible mounting point where the floor goes up over the diff. 

I'd like to cage the car eventually, but it's not in the budget right now. Getting work like that done in Australia is pretty expensive these days because you can't just knock a cage up in you backyard anymore, it generally has to be fabricated by a recognized chassis builder.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote ScreamerX Quote  Post ReplyReply Direct Link To This Post Posted: Feb/20/2021 at 4:42pm
Haven't seen anyone making a harness bar for older muscle cars.  If you can't use the location where the rear seat belts bolt to the floor as the anchor points for the shoulder straps on your 4-point harness - because it's less than a 45 degree angle - you enter a risk/reward decision.  

Two issues:  1st is the geometry of the pull of the seat belt against the drivers spine; 2nd is the ability of the drivers head to move if the roof collapses during a crash.

Most specifications for harness seat belts are that the angle of the drivers spine to the shoulder harnesses must be greater than 45 degrees to prevent spinal injury to the driver. Easy when mounting the system to a roll bar.  More challenging with short wheelbase cars like Gremlin & AMX.  Running < a 45 degree angle is a not even allowed by most sanctioning bodies. 

The other issue is that a four point system will not allow your head to move if the roof collapses without a roll cage.  Without a roll cage, it's up to you to weigh that risk.  

I run autocrosses, no roll bar, so the 4 pt is more to hold me in the car than to protect during impact.  Likelihood of a rollover is low, so its a risk I bear.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote WesternRed Quote  Post ReplyReply Direct Link To This Post Posted: Feb/20/2021 at 6:42pm
If I go to a sanctioned event, I need a 4 point harness if I run under 12 seconds, car runs high 11's, I don't need a cage until I'm into the 10's.

It will be interesting to see how things pan out at my local tack as it had just changed management and the new track operators are a subsidiary of ANDRA, our national sanctioning body. This might see them more rigorously apply the ANDRA regulations in the future.

I currently only run at our "off street meetings", which are basically test and tune sessions aimed at street registered cars. That issue here that some some safety things you require at the track are actually illegal on the street, so they are caught between rigorously applying the rules and turning too many cars away at the tack.  

I see the harness bars are quite popular for low level circuit and autocross type cars. Ultimately I'll probably end up caging it, but I want to tackle some more of the structural rust in the body first. Might be that I see the season out as is, we only have a couple of months to go and then see what pans out over the winter break.
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