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fastsc92
10-27-2008, 12:47 PM
For those that have a bar/cage and know the rules very well.... Is it acceptable to have a removable crossbar? This is a picture of Jim Demmit's car with a removable bar, which I like. Question is....is it legal?

I was going to buy a kit from S&W, but I think that I may make my own from chromoly and I think it'll be a lot cheaper than their $400 kit. I want to pass the bars through the package tray in the back to maintain some functionality of the rear seats. Any comments on the fit of the S&W kit and what their set-up looks like?

http://img.photobucket.com/albums/v325/fastsc92/Dcp_1059.jpg

joshbea6
10-27-2008, 02:43 PM
It is acceptable if the pins that hold it in place are NHRA approved pins, like the pins that go in the swing out door bars.

I am going to be doing the same thing in my 1990 SC (removable cross bar, swing out door bars, and rear seat saver bars).

You can get your drawings approved by NHRA if you want. Find your local NHRA representative and they can put you in touch with an NHRA engineer that you can bounce your ideas off so that you are not wasting money.

BLOWN38
10-27-2008, 02:48 PM
Definatly go thru the package tray like this.
http://i160.photobucket.com/albums/t172/MarauderTJA/RollBar6Side.jpg

And this guy says the cross bar can't be removable but I'm not sure on that. I'll look thru the rule book and try and find out.

The cross bar would have to be removable for us to be able to use the back seat. Which it would suck if you cant make it removable. But maybe you could put some padding around it to cover the pins.

fastsc92
10-27-2008, 02:58 PM
That's exactly what I was thinking. I can do what was shown in Jim's picture, which still makes the back seat functional, but not the most comfortable. I rarely have passengers anyways, but I want to keep it looking nice. I figure I can go through the package tray area nice and clean and tie into the trunk more.

I've looked through an older rule book and can't find anything that says that the center bar must be welded/connected. Worst case I'll just have to redo the cross bar.

David Neibert
10-27-2008, 03:08 PM
That's exactly what I was thinking. I can do what was shown in Jim's picture, which still makes the back seat functional, but not the most comfortable. I rarely have passengers anyways, but I want to keep it looking nice. I figure I can go through the package tray area nice and clean and tie into the trunk more.

I've looked through an older rule book and can't find anything that says that the center bar must be welded/connected. Worst case I'll just have to redo the cross bar.

Once the cage/rollbar is installed, you shouldn't allow passengers in the rear seat. Even with the cross bar removed the diagonal bars from main hoop to rear floor and the bars going into the trunk are a danger to passengers. BTW, the bars that follow the roof line and enter the trunk through the speaker deck are called "Pro Street" style.

David

BLOWN38
10-27-2008, 03:32 PM
We completely padded the roll bar in my dads marauder and wrapped it with some neoprene raps that they call RAPZ can get them from summit. It was a pain but I think it looks much better in the interior and prolly cuts down on the noise from the frame that is directly connected to.
http://i169.photobucket.com/albums/u216/blown38/padding2.jpg
http://i169.photobucket.com/albums/u216/blown38/padding1.jpg

And the cool thing about the marauders is you can pass the bar thru the child restraint covers
http://i169.photobucket.com/albums/u216/blown38/childrestraint.jpg

fastsc92
10-27-2008, 03:39 PM
Can the diagonal braces that go from the main hoop to the floor be omitted? Effectively making it a 6-point cage....

If those were gone, in addition to pro street style rear bars, you should have a much more usable rear seat.

BLOWN38
10-27-2008, 03:46 PM
You don't need the diagonal bars if you only going fast enough to need a roll bar, not a cage.

You need a side bar on driver side a hoop a cross bar and the rear hoop support bars to go quicker than 11.50 in the 1/4. Untill you get to the next speed/ time break to where you need a cage.

BLOWN38
10-27-2008, 03:47 PM
Can the diagonal braces that go from the main hoop to the floor be omitted? Effectively making it a 6-point cage....

If those were gone, in addition to pro street style rear bars, you should have a much more usable rear seat.

The only thing i can think why Jim has those is to be able to have the removable cross bar.

fastsc92
10-27-2008, 03:55 PM
The only thing i can think why Jim has those is to be able to have the removable cross bar.

Makes sense. What constitues a "cage". Sounds like the roll bar requirements are close to making it an 8 point cage already.

I've heard that a cage (9.99et) needs a window net, have the seat braced by the main hoop/crossbar and must pass a certification.

I only plan to need a roll bar, but I might was well add the diagonal bars, and the pass side bar while I'm already at it. Using chromoly tubing it can't be much more of a weight issue. If it were the .134" steel tubing then that's a different story.

BLOWN38
10-27-2008, 04:08 PM
Makes sense. What constitues a "cage". Sounds like the roll bar requirements are close to making it an 8 point cage already.

I've heard that a cage (9.99et) needs a window net, have the seat braced by the main hoop/crossbar and must pass a certification.

I only plan to need a roll bar, but I might was well add the diagonal bars, and the pass side bar while I'm already at it. Using chromoly tubing it can't be much more of a weight issue. If it were the .134" steel tubing then that's a different story.

A cage you would have the bar at top of windshield and bars that go down the A pillar, cross bars on both sides of car. I think there are different levels of cages. Like needing cross bars on the rear hoop supports and just basically bars everywhere.

like in this post. post #8http://www.sccoa.com/forums/showthread.php?t=93019&highlight=race+car

Wzenheimer
10-27-2008, 06:04 PM
When I had my 93' I made my own cage with the "Pro-street" style bars, thinking it would make my rears seats usable. However, like David N. said you wouldn't want to put anyone back there. Anyone back there would be so dangerously close to a BAR that they could knock their head really easily with normal driving.

If I were to do it again, I would do it like Jim had his with a swing out side bar, and a removable cross bar, with the supports down in the seats. Once you put in any type of "ROLL BAR" you will basically loose your reat seat for passengers, IMHO. You could still put things back there but people would be on the not so safe side. Using the bars down in the seats will leave your trunk totally stock and unaffected for use as well.

Chris

joshbea6
10-28-2008, 08:42 AM
When I had my 93' I made my own cage with the "Pro-street" style bars, thinking it would make my rears seats usable. However, like David N. said you wouldn't want to put anyone back there. Anyone back there would be so dangerously close to a BAR that they could knock their head really easily with normal driving.

This is why I'm going to do a custom rear seat so that I can take my 2 kids with me. I'm only going to use the center section of the seat and make the rear seat a 2 seater, instead of the 3 seater that it is from the factory. That way I can still take the kids while they are small and in car seats (extra protection).

Kurt K
10-28-2008, 11:11 AM
This is why I'm going to do a custom rear seat so that I can take my 2 kids with me. I'm only going to use the center section of the seat and make the rear seat a 2 seater, instead of the 3 seater that it is from the factory. That way I can still take the kids while they are small and in car seats (extra protection).
Maybe my kids' car seats are bigger than some, but fitting 2 of them side-by-side isn't going to buy you a lot of room. Plus, once the car seats are next to each other, then the 2 kids will be messing with each other....."your on my side" type stuff:D

I can currently only put one car seat in my back seat because my daughter is still in a rear-facing seat (which will only fit in the middle of the back seat when both front seats are occupied). Once she is old/big enough to face forward, I could put both car seats in the car.

fastsc92
10-28-2008, 12:23 PM
any passengers in my car would be adults and at most, one to two times per year. I think placing children in a situation like that is not the smartest idea. Just my opinion though

Kurt K
10-28-2008, 01:53 PM
I think placing children in a situation like that is not the smartest idea. Just my opinion though

I agree. I was just mentioning that I didn't think 2 car seat would fit with a cage....not that I would try it personally.

CMac89
10-28-2008, 01:59 PM
The swing out bar is legal for full bodied cars running 8.50s or slower. I'm not sure if you know the diameter of tubing that's required, but the swing out bar has to be 1 5/8" tubing with a .083" wall thickness (Chrome Moly.) You can use an NHRA approved pin or a 3/8" bolt affixed to a double shear. What I would do is get a clevis or a slide-sleeve. You need two inches of engagement for those, though.

You DO need to have the side (diagonal) bar on the driver's side only, for a roll-bar. Tubing size is 1 3/4" by .083" except for the adjacent loop support bar, which is 1 1/4" by .083".

fastsc92
10-28-2008, 02:28 PM
The swing out bar is legal for full bodied cars running 8.50s or slower. I'm not sure if you know the diameter of tubing that's required, but the swing out bar has to be 1 5/8" tubing with a .083" wall thickness (Chrome Moly.) You can use an NHRA approved pin or a 3/8" bolt affixed to a double shear. What I would do is get a clevis or a slide-sleeve. You need two inches of engagement for those, though.

You DO need to have the side (diagonal) bar on the driver's side only, for a roll-bar. Tubing size is 1 3/4" by .083" except for the adjacent loop support bar, which is 1 1/4" by .083".

I was refering to the diagonal bars that go from the main hoop to the tranny tunnel, not the door bars. I understand that at least the drivers side must be installed.

I was not aware that the door bars need to be 1-5/8" vs. 1-3/4". I can't find anywhere in the rulebook that says it needs to be 1-5/8's.

I guess an NHRA "approved" pin is a 1/2" x 2-1/2" pin, and a 1/2" bolt as the pivot. You can get swing-out kits complete for about $40 per side from Jegs.

I think we've cleared up all the other questions regarding the door bars. The main question is a removable center bar.

Using the density of the steel (.283 lb/in^3) and the length of tubing needed, I estimate that it'll weight approx. 60lb's for an 8-point set-up. Not that bad i guess. I dropped that amount of dead weight when swapping to skinnies in the front.

CMac89
10-28-2008, 02:55 PM
I was refering to the diagonal bars that go from the main hoop to the tranny tunnel, not the door bars. I understand that at least the drivers side must be installed.

I was not aware that the door bars need to be 1-5/8" vs. 1-3/4". I can't find anywhere in the rulebook that says it needs to be 1-5/8's.

I guess an NHRA "approved" pin is a 1/2" x 2-1/2" pin, and a 1/2" bolt as the pivot. You can get swing-out kits complete for about $40 per side from Jegs.

I think we've cleared up all the other questions regarding the door bars. The main question is a removable center bar.

Using the density of the steel (.283 lb/in^3) and the length of tubing needed, I estimate that it'll weight approx. 60lb's for an 8-point set-up. Not that bad i guess. I dropped that amount of dead weight when swapping to skinnies in the front.
I think there's a page in there, one or two passed the roll bar diagram, that states that. I don't remember if it's minimum diameter, or not. Obviously, 1 3/4" is stronger than the 1 5/8" tubing, so it's acceptable.

The loop support bar CANNOT be removable. Generally, if you can't find any information on a certain subject in the rule book then just assume that it is prohibited.

I'd stay with Chrome Moly to save weight. I know you can TIG weld, which is the only approved weld for Chrome Moly. Oh, yeah; no grinding, either. Sucks whenever you install a cage and get thrown out of a track for that. I've seen it happen.

David Neibert
10-28-2008, 03:01 PM
I was refering to the diagonal bars that go from the main hoop to the tranny tunnel, not the door bars. I understand that at least the drivers side must be installed.

I was not aware that the door bars need to be 1-5/8" vs. 1-3/4". I can't find anywhere in the rulebook that says it needs to be 1-5/8's.

I guess an NHRA "approved" pin is a 1/2" x 2-1/2" pin, and a 1/2" bolt as the pivot. You can get swing-out kits complete for about $40 per side from Jegs.

I think we've cleared up all the other questions regarding the door bars. The main question is a removable center bar.

Using the density of the steel (.283 lb/in^3) and the length of tubing needed, I estimate that it'll weight approx. 60lb's for an 8-point set-up. Not that bad i guess. I dropped that amount of dead weight when swapping to skinnies in the front.

It's going to end up weighing about 100 more pounds. Don't forget about the 1/8" X 6" x 6" plates that get welded to the floor pan at all rollbar/cage attachment points.

S&W also sells the swingout hinge kits.

David

fastsc92
10-28-2008, 05:53 PM
:(
It's going to end up weighing about 100 more pounds. Don't forget about the 1/8" X 6" x 6" plates that get welded to the floor pan at all rollbar/cage attachment points.

S&W also sells the swingout hinge kits.

David

I don't see how it can weigh an additional 100lb's, on top of the 60lb's for just the tubing. Each mounting pad will be 1.27lb's each.

David Neibert
10-29-2008, 11:44 AM
:(

I don't see how it can weigh an additional 100lb's, on top of the 60lb's for just the tubing. Each mounting pad will be 1.27lb's each.

I meant about 100 lbs total weight increase for adding a 6 point roll bar if using mild steel DOM tubing.

David

fastsc92
10-29-2008, 12:27 PM
I meant about 100 lbs total weight increase for adding a 6 point roll bar if using mild steel DOM tubing.

David

I plan on making it out of chromoly, so I can use .083 wall thickness. With a density of .283lb/in^3, the cross sectional area should be .456in^2. I estimate I need about 40' of pipe. That results in roughly 62lb's. Then add the plates which should be about 8lb's. For around 70lb total. I save about 38% of the weight if I use chromoly instead of the .135" mild steel.

boooster
10-29-2008, 02:23 PM
S&W can make your cage out of chrome moly just call them. The kits are not prefab they have to bend them. Ive still yet to install my cage however not like i need it

fastsc92
10-29-2008, 02:56 PM
S&W can make your cage out of chrome moly just call them. The kits are not prefab they have to bend them. Ive still yet to install my cage however not like i need it

I understand they have kits for our cars, but they want $400 plus $70 for shipping. I can make my own for far less than that, and taylor it to my car the way I want it.

Chromoly tubing isn't that expensive in my area and I should be able to get two 20' lengths to take care of what I need.