Cascade Crew

blue89 · Posted: Wed Mar 26, 2008 2:25 pm Post subject: Roll Cages

Does anyone have any roll cage experience? What can/can't you do? I know its generally not okay to tie them forward of the firewall. I also have heard its illegal to weld them to anything above the floor (like pillars and ceilling). But is there any thing sneaky you can do? A friend of mine said you can crush the roll hoop into the ceiling before you weld it to the floor. I also see alot that the rear part of the cage always ties into an L-bracket mounted on the tank hump.

Dewey316 · Posted: Wed Mar 26, 2008 4:33 pm Post subject:

It depends on what sactioning body you are building the cage for, NHRA has diffrent requirments, than SCCA or NASA or other racing groups. Your question is also pretty vague, So I am a little unclear what you are asking.

Xophertony · Posted: Wed Mar 26, 2008 9:34 pm Post subject:

your looking to get the MOST chassis stiffening you can get out of that cage right? having it pressed into the roof would help, but may be illegal. welding it to the roof would [be better, but may be illegal depending on your sanctioning body. you may however, be able to get away with it anyway. you could put foam padding on the cage, unless it (the foam) was removed no one would see the welds. though it would probably show on the top of the roof.

as far as the rear mounts go, try and tie them in directly above the rear over tank "frame" rails. there are two unibody rails that run back there and support the bumper. having your cage tied in here MAY (i am no engineer) help the car absorb more shock in a rear end collision. if sub frame connectors help i am sure a cage would be even better.

if you can get the front mounts tied in to the sub frame that would be best as well, but i am sure you already knew that.

Twilightoptics · Posted: Wed Mar 26, 2008 9:35 pm Post subject:

I think if most cages will pass most guidelines. If one is more strict, it will pass the lessers fine. I'm familiar with just the NHRA setups. You'll need to get a rule book to outline where the bars go.

Cages are welded to an 8x8x1/8" plate, welded to the floor. You can tie things to them like braces for this or that and rear axle linkage, however, you have to have sufficient framing already attached to the rear to propel the car.

You don't want any "pre-crushing" if your bars. That's asking for trouble if you do actually have to use it. If you have trouble welding the top of the hoop, you can cut out the floor... put the hoop through it to gain access to the top. Weld it... then bring the hoop back up, weld in your plates, bar to the plates, and go. Do no tie the bar to the firewall. Most bodies have strict rules about the firewall. IE If you remove 'x' amount of material or 'alter' said amount of material on the firewall, you have to run a cross brace from forward down bar to forward down bar.

Rules are also different if you're going cage vs rollbar.

Spohn actually has a good PDF on installations for NHRA/IHRA S&W Cages.

http://www.spohn.net/instructions/Cages.pdf

Twilightoptics · Posted: Wed Mar 26, 2008 9:42 pm Post subject:

Tony. Once a cage is welded to the floor... a full 10 point cage... you wont notice much if any stiffening by trying to weld it to the roof or other various places. Welds must be visble for inspection. Padding is to be only where the drivers helmet may hit within a given specification of distance.

And yes.... weld the cage with the suspension level and loaded!

blue89 · Posted: Thu Mar 27, 2008 6:49 am Post subject:

I had a hunch that once you had a good connection with the floor that trying to tie it into the roof was a mute point. Would it be safe to say that when done properly the roof would have almost no strain on it?

How do you ensure that the body is straight with the suspension loaded? I am going to go with an NHRA approved cage so I can ensure making runs down the strip. Cause if you can't do that, whats the point? Wink

Do you think it would be safe to get a 6 point cage from summit and then update it later to an 8/10 point if need be? How much weight do these add? I see people doing gusseting on cages, are these legal?

blue89 · Posted: Thu Mar 27, 2008 9:09 am Post subject:

http://www.spohn.net/?action=product&pid=1211

You can convert a 8 point to 10 with an add-on piece. Sweet! I think I'm going to go that route.

Xophertony · Posted: Thu Mar 27, 2008 10:29 am Post subject:

Twilightoptics · Posted: Thu Mar 27, 2008 4:52 pm Post subject:

Just do it on as level ground as you can and weld it. It's as critical as subframe connectors... which isn't THAT critical.

8point roll bar. 6point doesn't count.

If you plan to "convert" remember.. you can't cheat and lower the main hoop... to weld the halo on.

Pick the version you want to go with, and do that all at once.

blue89 · Posted: Fri Mar 28, 2008 7:23 am Post subject:

How do you weld the halo to the top of the main hoop if you can't even see the top? I don't see how the cage can go together in the car to allow access to all the weld points.

Twilightoptics · Posted: Fri Mar 28, 2008 11:39 am Post subject:

blue89 · Posted: Fri Mar 28, 2008 12:13 pm Post subject:

Thats it? Thats all you have? Wink

Local shop advised that I buy one premade to save costs and they will install it for a couple hours of shop time. So do you need to have a shop be NHRA approved to have them install it and be track worthy?

izcain · Posted: Tue Apr 29, 2008 8:30 pm Post subject:

As long as they build it to spec there will be no issues although I can garuntee that even the premade cages will take more then just a couple of hours to install. Once you get under a set time you will have to get the cage inspected by NHRA officials and they stamp in a certification that is good for a set amount of passes.

DBL_TKE · Posted: Tue Apr 29, 2008 11:31 pm Post subject:

I am only firmiliar with NHRA cages but you can weld them to the body and such as you wish, just don't grind down the welds, it's not allowed.

Get yourself a rulebook. there's a bunch of little technical details that can get lost in translation through second hand knowledge.

abd BTW an SCCA cage is not NHRA and visa versa. You'll be building yourself a damn near birdcage if you want it to be good for multiple sanctioned bodies.