6 point roll bar

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6 point roll bar

Postby 72vega383 » Wed May 08, 2013 6:24 pm

Looking at fabricating a 6 point roll bar for my 72 vega. It has a stock interior and would like to keep it that way. Engine is a 383 stroker with High rise and race cam. Approx. 500hp not sure how fast it will run. I want the bars to pass tech at the tracks so looking for info on how to do it right. Would like to use swing out or removable door bars and have access to rear seat also as it will be mainly a street car.

What material? I will be using a Lincoln 180 with gas.
Where should all the bars be placed?
I want it to barely be noticeable unless your close I have seen them done where I cant even notice until I get real close or in the car.
How do I go about getting it certified?

Thanks in advance!
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Re: 6 point roll bar

Postby speedphreake » Wed May 08, 2013 8:09 pm

Best thing to do is get a nhra or ihra rule book for specifics. You can look at my build page to see how I did mine. It's mostly a street car that runs mid 10's. I have swing out door bars on both sides that i remove for street driving. You won't need to get certified until your fast enough to require a full cage.
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Re: 6 point roll bar

Postby 72vega383 » Wed May 08, 2013 10:54 pm

I am thinking of making the cage out of PVC pipe for mockup and then bend out of 1 3/4" 1/8" wall mild steel. If I can't get dimensions for a completely functioning all stock interior vega.
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Re: 6 point roll bar

Postby speedphreake » Thu May 09, 2013 7:35 am

i don't think 1/8" will pass, it needs to be .134" wall tubing unless you go chromoly or dom tubing. I got mine from S&W race cars. The main hoop fit well and the rear bars I custom spec'd so it would clear the rear seat and follow the rear window line to keep it out of sight from the side.
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Re: 6 point roll bar

Postby 72vega383 » Thu May 09, 2013 7:45 am

I am not exactly sure but from what I seem when I search up nhra rule book it shows that if using mild steel it must 1 3/4" o.d and .118" wall.
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Re: 6 point roll bar

Postby stage169 » Thu May 09, 2013 9:42 am

People have posted this a few times here.

Image

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Re: 6 point roll bar

Postby chevyart » Thu May 09, 2013 4:45 pm

hey 72. just call SW race cars in pennsylvania and buy one made up, ready to go and you can add the swing outs(maybe they will weld them in). they practically invented the vega roll bars and cages going way back into the 1970s. what they make will fit and will be legal. art
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Re: 6 point roll bar

Postby chevyart » Thu May 09, 2013 4:47 pm

hey jeff(speedphreake) watch out. im coming to get you this year. if the 377 dont work, in goes the 383 art
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Re: 6 point roll bar

Postby speedphreake » Thu May 09, 2013 9:12 pm

you will need dom tubing to cut it that tight. manufacturing tolerances vary, then when the bends are made you loose a little. as far as I have seen, most roll bar suppliers us .134 to make sure the bar passes and sonic check for wall thickness.

Art,
I have a few surprises up my sleeve this season... :dance:
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Re: 6 point roll bar

Postby chevyart » Thu May 09, 2013 9:53 pm

jeff i guess if its those switches you hit going down the track, i am a dead man. see you soon art
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Re: 6 point roll bar

Postby 72vega383 » Tue May 14, 2013 4:19 pm

i bought some pvc plumbing pipe and different angle fittings 2". hoping to fab up the roll bars out of that then duplicate in 3/16" wall 1 3/4" steel tubing. If i am understanding correctly the plates that need to be welded to the floor pans dont have to have the bars centered correct? the tubes can be all to one side of the plate?

thanks
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Re: 6 point roll bar

Postby speedphreake » Tue May 14, 2013 8:43 pm

Thats how all of mine are.
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Re: 6 point roll bar

Postby chevyart » Wed May 15, 2013 3:30 pm

when i did my nova in the 90s i had an 8 point cage installed, and it was just welded to the floor pans(thin stuff) what i did was made plates for the underside of floors and bent them to match the contour of floor and bolted them together with 4 bolts on each plate. just like a metal sandwich.im sure it made things stronger than just the plates on cage welded to floor art
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Re: 6 point roll bar

Postby 72vega383 » Tue May 21, 2013 10:09 pm

ok so i am thinking i will make my roll bar. Here is what i am thinking

Main hoop with rear runners that will clear back seat (measurements provided by speedphreake thank you so much!)
Swingout door bars and rocker bars that will go from main hoop to stationary part of door bars. hoping to run these very low to the ground probably almost rsting on the floor and maybe weld to it to mimic subframe connectors better and to tie in the cage better since the door bars will be swingout!

Would anyone be willing to provide me with a drawing with angles and measurements of the main hoop? after i get he main hoop an rear runners made and welded in the front door bars and rocker bars should be easy to make up and measure for.

I appreciate the help guys!
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Re: 6 point roll bar

Postby speedphreake » Wed May 22, 2013 7:10 am

Just order one from S&W like I did. The main hoop fits very well and they made the rear runners to my spec. The swing out bar kit I got from A.R.T.
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