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Old 02-18-2008, 05:39 PM   #21
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Arent they the same bolts that hold the seat belts in place? I would be more worried of the bar yielding
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Old 02-18-2008, 05:50 PM   #22
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no, they dont hold the seat bets, but they look bigger/thicker IIRC
anyways, i get what Savagina is saying and it makes sense, it was not engineered to withstand any kind of force front to back, i just never thought of that nor have i ever seen one fail...it makes me curious to know if indeed he is right, id hate to find out this is the case while chewing on my steering wheel after an accident
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Old 02-18-2008, 06:50 PM   #23
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Quote:
Originally Posted by whaaamx5 View Post
no, they dont hold the seat bets, but they look bigger/thicker IIRC
anyways, i get what Savagina is saying and it makes sense, it was not engineered to withstand any kind of force front to back, i just never thought of that nor have i ever seen one fail...it makes me curious to know if indeed he is right, id hate to find out this is the case while chewing on my steering wheel after an accident
The test would be pretty destructive to the test car. The issue is that the brace was meant to take forces in the up and down direction as that part of the car flexed; apply a forward-back force and it all goes to hell. You could argue that the bolts are pretty beefy, sure, but would you trust your life to that assumption? I sure as hell wouldn't.

I wouldn't ride passenger in a car with harnesses wrapped around it, and if I were teching a car at an HPDE, I'd tell the owner to run his OEM 3-point belts or not run at all. That bar wasn't designed to take the loading forces of a set of safety belts.
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Old 02-18-2008, 07:16 PM   #24
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Do not use the cockpit brace as a mounting point for the harness. The cockpit brace is just a length of metal flatstock covered in rubber. It's not designed to take the force of a harness on it during an impact. It'll probably bend or pull those 2 bolts right out. The HD harness bar I run is bolted in 4 places, not 2, and is DOM tubing. That cockpit brace lets go, your in for big trouble. Your face and torso is worth the $100 to get the right piece.
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Old 02-18-2008, 07:35 PM   #25
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i understand, and it makes sense, i just never thought of it...it is only a temporary solution
i was considering welding a cross tube on my roll bar, any ideas of how thick i should go?
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Old 02-18-2008, 07:40 PM   #26
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1.5" DOM will be fine. Pretty sure that's what HD uses.
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Old 02-18-2008, 07:51 PM   #27
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My harness bar on my HDHC is, I believe, 1.75"x.120
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Old 02-18-2008, 07:54 PM   #28
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Quote:
Originally Posted by Savington View Post
My harness bar on my HDHC is, I believe, 1.75"x.120
If i was welding in the harness bar and I had a 1.75" bar like the HDHC i would use 1.75" DOM for the harness bar. If I had a sport model with 1.5 I would use 1.5. If i was building a bolt in harness bar I would use 1.5".
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Old 02-18-2008, 09:01 PM   #29
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Quote:
Originally Posted by cjernigan View Post
If i was welding in the harness bar and I had a 1.75" bar like the HDHC i would use 1.75" DOM for the harness bar. If I had a sport model with 1.5 I would use 1.5. If i was building a bolt in harness bar I would use 1.5".
i was thinking closer to 2", and to everyone who was bitchin bout the 4 pt. i never said anything about a 4 pt., i would likely run a 6pt. I don't think I'll do much ducking/rolling if i had a 3 pt in anyway, i highly doubt i'm strong enough to overcome the G's of a rolling/flipping car. Besides I'm gonna make a rollbar for the car eventually anyways
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Old 02-18-2008, 10:24 PM   #30
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Yeah, I bent a factory seatbelt brace pulling on it.. I would NOT trust my life to that piece! They make harness bars for our cars roll bars for a reason, if you're not going to use proper safety equipment then use the factory installed stuff.

Reminds me of the honda owner who secured his 4 point harness shoulder straps to the rear seat belt buckle...



Read last post: http://www.solsticeforum.com/forum/f42/4-point-21909/
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Old 02-18-2008, 10:30 PM   #31
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fourwhls = LBJay ??
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Old 02-18-2008, 10:58 PM   #32
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Quote:
Originally Posted by mazda/nissan View Post
I don't think I'll do much ducking/rolling if i had a 3 pt in anyway, i highly doubt i'm strong enough to overcome the G's of a rolling/flipping car. Besides I'm gonna make a rollbar for the car eventually anyways
You've just been told that running harnesses without a rollbar in an open car is a lot like signing your own death warrant, and you're still going to do it anyway?

w/e. Have fun dying.
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Old 02-18-2008, 11:21 PM   #33
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As an FYI - Hard Dog makes a harness bar that attaches the same way as the cockpit brace...except it has two extra bolts running in from the side. A roll bar is not required for this bar...not saying it isnt a good idea though.
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Old 02-18-2008, 11:36 PM   #34
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Quote:
Originally Posted by miatanutz View Post
As an FYI - Hard Dog makes a harness bar that attaches the same way as the cockpit brace...except it has two extra bolts running in from the side. A roll bar is not required for this bar...not saying it isnt a good idea though.
Same said bar is also significantly larger than the cockpit brace is.. specifically designed for harness attachment.
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Old 02-18-2008, 11:37 PM   #35
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Quote:
Originally Posted by elesjuan View Post
Same said bar is also significantly larger than the cockpit brace is.. specifically designed for harness attachment.
Yes indeed. its rather stout, I owned one.
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Old 02-19-2008, 08:36 AM   #36
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Some sanctioning bodies may not allow harnesses without a rollbar. I know NASA keeps an eye on that stuff, the events I've attended anyway.
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Old 02-19-2008, 10:15 AM   #37
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Quote:
Originally Posted by Savington View Post
You've just been told that running harnesses without a rollbar in an open car is a lot like signing your own death warrant, and you're still going to do it anyway?

w/e. Have fun dying.
and do you really think i'd fair much better if my head was skidding across the pavement with a 3pt. vs 6pt.? as already stated i would never be able to pull my head down in a rolling car anyways. And don't worry about the cockpit brace, i don't have one

would there be a safety difference between having a separate bolted harness bar and welding a horizontal bar onto my future roll bar?
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Old 02-19-2008, 10:23 AM   #38
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Quote:
Originally Posted by mazda/nissan View Post
and do you really think i'd fair much better if my head was skidding across the pavement with a 3pt. vs 6pt.? as already stated i would never be able to pull my head down in a rolling car anyways. And don't worry about the cockpit brace, i don't have one

would there be a safety difference between having a separate bolted harness bar and welding a horizontal bar onto my future roll bar?
You wouldn't have to fight it depend on which way you were rolling. Id rather have a chance of being able to get out of the way rather than no chance at all. You would be surprised what a human can do when the adrenaline get's pumping. You are getting some good advice here take heed.

Don't use any harness without a true roll bar.. it's simple really and makes good sense.

If you do decide to go with a harness and no roll bar please keep a camera running i'd like your skull pop like a squished M&M if you ever roll over. Make sure you put in your will that you want the video posted on youtube so other ricers won't make the same mistake.


KTHNXBYE
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Old 02-19-2008, 10:27 AM   #39
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probably not, i plan on welding something to my roll bar
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Old 02-19-2008, 11:29 AM   #40
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Quote:
Originally Posted by MX5-4me View Post
You wouldn't have to fight it depend on which way you were rolling. Id rather have a chance of being able to get out of the way rather than no chance at all. You would be surprised what a human can do when the adrenaline get's pumping. You are getting some good advice here take heed.

Don't use any harness without a true roll bar.. it's simple really and makes good sense.

If you do decide to go with a harness and no roll bar please keep a camera running i'd like your skull pop like a squished M&M if you ever roll over. Make sure you put in your will that you want the video posted on youtube so other ricers won't make the same mistake.


KTHNXBYE
once again you damned hippies, i don't care if i have enough adrenaline to do **** push-ups the human body is only capable of doing so much

whaaamx5, i'm pretty sure bolts would be safe enough, considering i may even buy my own roll-bar. I am pretty certain that i don't have to worry about
Quote:
Originally Posted by Savington View Post
1. It's bolted down with two bolts, and the harnesses pull in the wrong direction, which means those bolts will just bend. Bolts are strong in the direction they apply force, not perpendicular to that direction.
if that were the case how would wheel studs work?
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