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Extending a 4 point roll bar?


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My car is in the shop having some coilover adapters installed/welded and I asked the owner to weld in my 4 point roll bar while it's all gutted out.

 

Is there anything wrong with building off of the roll bar? Adding a halo, a-pillar bars, and a couple cross braces going down in the hatch. Just a simple track day/ street cage, perhaps an occasional auto-x, but I don't intend to run in any serious competition.

 

 

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If you want door bars that's a funky one to install them on. They used to make a cage for that Autopower bar, but the bar had little extensions that the A pillar and door bars plugged into and then a bolt held the joint together. I didn't like it much, but you could buy one at one time (maybe still can???).

 

If you could buy the extra pieces, welding the little tubes onto the bar you have would be pretty simple.

Edited by JMortensen
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Doesn't the rollbar HAVE to go to the floor with 6"x6" footplates to be NHRA legal (I''m asking)? When I first built my car, I didn't worry about safety certification-now I have to do it all over again since I started drag racing!  I've got one of those Auto Power rollbars like that and I've considered adding door bars to it too-I honestly think it would be fine structurally-the inner fenders have compound bends that look much more rigid than the thin, flat floor.  But I'm not gonna bother since it wouldn't pass tech.  Those little bars are really just dead-weight customizing pieces or a place to attach a shoulder harness (my excuse).  I know you said that you weren't gonna do anything serious,but plans change as you enjoy your car more and more, then you gotta tear it all down and break paint and throw sparks and iron filings to re-do it.  My local tracks overlook most safety rules - even helmets, and many of the other drivers race with a beer between their knees, but if I ever got a chance to do a Pinks, Passtime or Drag Week, you know I'd jump on the opportunity, and I'm sure those guys want you to be safety cert-ed.  I'm tiring of re-doing things I should have done right the first time!  So, give some thought to doing a legit rollbar-I wish I had.  If I had the guts to rip back down to bare metal I would build (likely have built) a cage that was NHRA cert-ed to 8 seconds and met SCCA IT specs - that standard would even qualify you for a fun trip to Bonneville.  Shouldawouldacoulda.

Edited by RebekahsZ
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johnc, JMortensen, cobramatt-I've seen bunches of threads that pooh-pooh footplates on the inner fenders.  I like how much room my fender-footed roll bar allows in the interior-I'd like to keep it if it is legit.  For SCCA (and by chance NHRA), do you think I can keep it as it is?  What is your interpretation? 

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The SCCA Autocross rules are kinda vague and not to specific.   It's basicly left up to the specific club to decide if what you have will pass tech.  

 

Section 3.3.2 (page 34) which refers you to Apendix C (page 241)

http://scca.cdn.racersites.com/prod/assets/2012_Solo_Rules_May.pdf
 

When it does get specific, in reference to full cages, it refers you to the club racing rules.

 

Section 9.4 (page 114)

http://scca.cdn.racersites.com/prod/assets/2013%20GCR-%20January.pdf

 

It's my experience that Autocross clubs aren't too picky, as long as things look like they are well made.  I actually have one of the Autopower full bolt in cages with the door bars, but I decided to only use the roll bar section because the full cage would require me to fully gut the car and go with a racing dash, which isn't something I wanted to do.   I am not using the door bars either because they take up too much space and aren't going to add a significant amount of stiffness to balance the loss of space or extra weight.  

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Nobody is going to hassle you over that bar at an autox. I ran it for 8 years or so, never heard anything pro or con about it. It used to be legal for road racing, so no doubt there were a lot of ITS cars running it. Not sure if they were grandfathered in or if they had to replace the cage or what. It also doesn't connect to the strut towers. If you're going to put in a cage, it might as well stiffen the car.

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Thanks for the links-I looked at them.  I didn't find any prohibition or advice in the GCR to state whether the rollbar can mount on the fenders or not.  I didn't find any reference to where the main hoop had to mount whatsoever.  I also found only a reference to the maximum footplate required, not a minimum.  I know NHRA specifies 6" X 6" - read that this week, but I haven't seen a requirement for floor mounting in their rules either.  Maybe this will work out after all.  Listening for more advice. 

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It's in there. The Appendix C thing says attach to the frame if possible, and the next part says attach to the floor for unibody. Still, for an autoxer, it won't make a difference. For a road racer, the rules are different and they don't really give as much leeway.

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Argh, hidden in an appendix! If I want to have the option of going to Atlanta for a road racing lesson with cobramatt, I want him to feel safe. Believe it or not, i care about having credibility with this site's "royalty." Not being sarcastic. I think I'm gonna bite the bullet next year and go ahead and have a legit cage made once and for all. Next winters project. Better get back to this winter's. thanks for letting me thread jack.

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Thanks, Josey.  Its not the money that is delaying the project-it is dealing with the dashboard and the windshield.  How about I pay you $500 to pull my dash and reinstall it (and tidy up all my shoddy wiring) after the cage is built?  I can only imagine the gremlins I'm gonna have after that!  Honestly, that is my hold-up.  Also, not sure how to run the knee bar in a way that lets me pull a heater core if it starts leaking after the cage is in.  I want it all welded in "one and done."

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Thanks, Josey.  Its not the money that is delaying the project-it is dealing with the dashboard and the windshield.  How about I pay you $500 to pull my dash and reinstall it (and tidy up all my shoddy wiring) after the cage is built?  I can only imagine the gremlins I'm gonna have after that!  Honestly, that is my hold-up.  Also, not sure how to run the knee bar in a way that lets me pull a heater core if it starts leaking after the cage is in.  I want it all welded in "one and done."

 

Haha, if you lived closer, I'd gladly give you a hand!

 

What do you mean my "knee bar"? The door bar? I"ll be putting swing outs on mine if / when I ever cage it, and leaving them out unless I'm going to the track.

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The knee bar is a bar that runs across the car below or above the dash.  May not be required for NHRA, but is required for SCCA.  It comes into play when you get t-boned.  The only thing that keeps a car from getting squished in the middle is the firewall and the cowl.  If you run it above the dash, it stays out of your way and doesn't bang your knees, but it doesn't contribute as much impact protection.  If I dive into a cage next winter (got enough on the list for this winter), I'm gonna want to have it satisfy everybody.  I will likely compromise on my door bars, angling them down a lot in the front and keeping them as low as is reasonable in back.  I don't want to do a removable bar-just something else to fool with the night before I go to the track - which I hope, this year, is a lot.

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OK, I'll get on my soapbox...

 

Do not put a full roll cage in a car unless you wear a helmet every time you drive it.  In a 240Z the door hoops or halo bar will turn a minor accident into a concussion very easily.  And the specified SFI padding won't help much because that padding is designed to work with a helmet, not a bare head.  Don't believe me?  Take a baseball bat, wrap it in SFI padding, and have your best friend hit you in the side of the head with a 25 mph swing.  In a real accident it would be like Barry Bonds taking a full swing into your head. 

 

Make a decision now before spending money on a roll cage or bar - is this a race car or a street car.  You will not be able to build a safety cage to satisfy NHRA, SCCA, and street driving requirements.  It just can't be done safely.

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The Autopower cage is legal for ITS and the Autopower roll bar turned into a cage for ITS would also be legal assuming the mounting plate requirements were met at the time.  Remember, back then SCCA only required a single door bar.  Those cars would have been grandfathered until I think 2008.  But, by then the E36 so totally dominated ITS that very few true ITS 240Zs were left.  Most of those left updated their cages out of fear of getting hit by 2,900 lb.s BMWs... :-)

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Do not put a full roll cage in a car unless you wear a helmet every time you drive it.  In a 240Z the door hoops or halo bar will turn a minor accident into a concussion very easily. 

 

 This was another reason why I did not use the full cage.   With the stock seats (on custom rails) my helmet hit the halo bars causing me to have to lean my head towards the passenger side. With racing seats this might not have been a problem, but I didn't want to take the chance.

 

Also if you do a full cage, putting the OEM dash and all the heater items back in the car is EXTREMELY difficult.   It's not impossible, just requires alot of fab work.   Much easier to do a racing dash (saves a ton of weight to).

 

The other thing is that, for track days or HPDE training, you really don't need any of that stuff.   It's overkill unless you have serious plans to race.

 

Street car or "RACE" car.   Pick one.

Edited by Apollyon12
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