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Fritz Flynn 02-27-14 12:54 PM

NASA ST2 Roll cage questions
 
3 Attachment(s)
I'm having a cage installed in my car for ST2/TT2 and the rules appear pretty open ended and the cage builder isn't experienced in building SCCA or NASA cages. The rear hoop section is fine and already passed the scrutineer/tech but the front section is currently being installed and after see some pics I had some concerns.

Here's what he's done so far:



My concerns:
Can the front bar in the halo or bar running above the window be bent in the center and be two bars welded together?

Can the halo have a vertical bar running down the middled or running from front to back in the upper halo.

Is just one passenger door bar legal and is there a height requirement

Is there a height requirement on the drivers side door bars

Any help or suggestions would be MUCH APPRECIATED!

Thanks!

RockLobster 02-28-14 12:13 PM

Fritz,

I don't like (and i think most inspectors would agree) the fact that that connector between the two forward hoops (the one running along the top of the windshield) is two pieces. I'd have that one cut out and re done as a single piece. I see no reason it cant be done that way. It can have bends in it. Most do to maximize visual field and minimize clearance to the roof. The rules say "A bar" which to me says 1 piece.

The center bar running from main hoop to front tie is fine. Added members are accepted as long as the basic components meet the rules and they do not hinder egress.

I'd also be inclined to question the door bars. I think it would be worth it to just add a 3rd door bar on the drivers side and a 2nd bar on the passenger side. They can be double bent nascar style to maintain the clearance you currently have with the low bars. Add a couple of vetical ties and you are done. As you noticed there is nothing in the rules but for your own safety you really want good side impact protection and with safety items walking the lines just ends up with tech shed issues at the track and a potentially early exit from an event. You may have to get creative in modifying those pretty door panels but you will thank yourself in a wreck.

Another note of caution for you. NASA is very particular with full welds (not that i see any) but i tell everyone who asks about cages this. No weld gaps are allowed and it's a zero tolerance sort of thing. I've failed numerous "SCCA passed it!" cages for weld gaps...it makes drivers very disgruntle but it's very high on the NASA safety requirements.

Chad M
Chief of Tech NASA MW
Tech NASA Central

gracer7-rx7 02-28-14 12:25 PM

Inexperienced cage builders that can't read the NASA or SCCA rules books themselves frighten me.

What Chad mentioned is correct.

The side bars on both sides are not legal. Nor are they particularly good. You should (check the specs for exact requirements) do Nascar bars on the driver door so you have maximum clearance to side impacts. Pax bars can be a simple X bar but if you are going to have people in that seat, I'd go ahead and do Nascar style bars like on the driver side.

While the tubing and tightness to the body contours look pretty nice, I'm more curious about how the cage legs are reinforced where they meet the floor pan.

Isn't there a sticky on cages somewhere in this section?

RockLobster 02-28-14 02:19 PM

RX-7s especially FDs tend to need to have holes cut in the roof to complete welds for the top of the upper bar areas at the B an A pillars. Even the FC (which is far better than the FD in terms of interior room) i had to have my roof cut to have the welds completed on my racecar.

RawrX8 03-07-14 08:09 AM


Originally Posted by RockLobster (Post 11689019)
RX-7s especially FDs tend to need to have holes cut in the roof to complete welds for the top of the upper bar areas at the B an A pillars.

Or you can bore a hole in the floor, tack the base plates, finish the cage and dotco welds away from base plates, drop the cage through the floor and weld with tons of room.

Fritz Flynn 03-09-14 09:51 AM

Thanks for the info guys. I've spoken to a few people and for the most part I think I'm fine.

The front halo bar isn't two pieces so no worries there.

Gian 03-09-14 02:21 PM

You may be fine rules wise. But one thing to think about. In ST cars are going much faster. Your door bars scare me. I would have a hard time being on a track with a bunch of really fast cars with the way the bars are in your pictures. Go the extra step with a 3rd bar (at lest) just for your own safety.


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