swing out bars vs. body flex

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swing out bars vs. body flex

Postby rtm » Sun Feb 19, 2012 12:25 pm

I was thinking of installing a swing out kit on my diagonal braces (8 pt. rollbar ) for ease of entry/exit.
I'm not getting any younger, so I'ts kind of a pain to manuver around them.
my question is, how much will it affect chassis flex from side to side.
car also has subframe connectors made from 1&1/2" x 2" rectangular stock.
the 406 produces 500 + FT. LBS. torque @the flywheel.
the jegs swingout kit is NHRA legal for cars running 8.99 or slower (I think that's what I read).
I will obviously never approach that w/ my combo.
not cutting anything yet, just wanted some experienced opinions (or yours too, LOL :lol: )
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Re: swing out bars vs. body flex

Postby cjbiagi » Sun Feb 19, 2012 2:01 pm

Ok, I admit that I don't know that much about roll bars but it seems to me that by not having the bar directly tied into the rest of the cage or body you are really going to lose the integrity of that particular bar. If it swings out and just is pinned to the other part is it really doing much in terms of strengthening the body? I can certainly appreciate your concerns about getting older though :(
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Re: swing out bars vs. body flex

Postby spencerforhire » Sun Feb 19, 2012 4:02 pm

Even in an 8-point cage, the door bar is not there to prevent chassis flex; it's there to protect the driver in the event of a roll over or crash. If you have any diagonals in there, they along with the subframe connectors should keep things from flexing too much. Adding the swing out bar shouldn't be a problem. If only I could do a swing-out bar to aid entry and exit; my cage is 14-point with an x-brace through the door opening that I have to drag my 275lb. 6'1" body(with bad knees)up and over! Not a pretty sight....
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Re: swing out bars vs. body flex

Postby Fasterthansome » Sun Feb 19, 2012 5:30 pm

The door bar isnt there to prevent chassis flex? Ok so its there because it protects the driver BUT it plays a huge roll in preventing chassis flex. A good swing out kit has a tight fitting pin and collar that will keep the stiffness.
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Re: swing out bars vs. body flex

Postby rtm » Sun Feb 19, 2012 5:48 pm

Thanx 4 replies,
as usual, I end up more confused than I started. (I tend to over think things) :bang:
If these swing out kits are NHRA legal for a WAY faster car than mine,
logic would dictate that the structural integrity would not be compromised, but..........
wouldn't that SOLID door bar be ALOT stronger than a joint with a bolt, no matter how tight the joint/bolt combo?
Not trying to start an argument here, just (probably) overthinking things AGAIN :oops:
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Re: swing out bars vs. body flex

Postby chevy art » Mon Feb 20, 2012 1:49 am

yo rtm. the other guys are right on. in my 67 nova i have a 8 point cage with the Morose swing out. i have subframe connectors and my car runs in the 10,s with 14 inch slicks and i assure you there is no chassis flex because i use a swing out.. car had about 525 horses. new engine has a tad over 600 horses. still not worried about flex, but i will see in a month or so. the moroso one is a real beauty, but i dont think they make it anymore, bur their custom shop may still make it. its a spring loaded piece like a bolt action on a rifle and is nice to use. let me know and i can check with moroso for you. no more overthinking brother, you may blow a fuse art
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Re: swing out bars vs. body flex

Postby rtm » Mon Feb 20, 2012 8:55 am

hey art, check into those spring loaded units for me (us).,
thanx man :th:
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Re: swing out bars vs. body flex

Postby chevy art » Mon Feb 20, 2012 11:19 am

yo rick. im on the case ill get in touch with you real soon. hope all is well. ill get up to see you in the very near future. talk soon art
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Re: swing out bars vs. body flex

Postby cjbiagi » Mon Feb 20, 2012 8:54 pm

See, I told you I don't know much about roll cages :oops: I still think there has to be something lost by not having it welded, but it may be insignificant according to what everyone else thinks. So, based upon all the other comments I guess I wouldn't worry about it.
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Re: swing out bars vs. body flex

Postby chevy art » Tue Feb 21, 2012 2:09 am

cj you are right too. im almost positive that swing out bars are not acceptable for cars going 9.99 and faster (certified chassis) i guess if they wont allow them it is because they are not as strong as the solid roll cage side bars.i myself would rather have my cage all one piect, but my big ass wont get in the car without the swing out bar. im also installing a removeable steering wheel in race car this year. that also makes it very easy to get in and out. sure wish i could get a lazy boy chair in there also to snooze while i wait in staging lanes art
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