Cage Rules/Specs

[RADustin]

Guys,

This is my first post but I've been a lurker for some time. I'm planning out the build on my '64 Nova. I'm going to make the dash removable and I want to cage it mostly for strength but also to make the car legal. I'll do subframe connectors but I don't want to completely hack the floor out. I'm not going that hardcore. Power will be in the 600HP range, maybe more but no less. The car will be mostly a street car but I want it to be track legal so I can really enjoy my labor. I'd like to keep as much of the backseat as possible but I realize I'm greedy.

I certainly want it to be legal for NHRA and was going to start with a prebent cage from chassisworks and then add bars to make it legal for some road action. I'm originally from New Orleans LA and will be moving back there in a few years, probably about the time my car is done. But either way I'm in Houston now and MSR isn't far away as is NOLA motorsports in New Orleans. So I have tracks available but I'm just not sure how they operate but I do understand that the track doesn't really mandate the rules as much as the person/club who is renting it for their event.

What rulebook are you guys building your cars to who are doing time attack style events at reputable road tracks? I will never run door to door so I think building the car to FIA Appendix J standards is way too much. I tried to lookup some SCCA stuff but it almost seems like anything NHRA legal is SCCA provided the tubing is thick enough.

So what do you guys think? What rulebook(s) are you all using and are you running into any problems?

Thanks!
-Dustin

[parsonsj]

I went down that road a while back. Here's what I did:

http://www.superchevy.com/technical/chassis/frame/sucp_1106_chevrolet_camaro_custom_roll_cage_instal lation/

An excerpt:

Speaking of books, the first thing to decide about the cage is the proper diameter and wall thickness of the tube itself. The NHRA requires 1 5/8-inch tube with .083 walls for 4130. NASA’s rulebook has a whole section on tubes and wall thickness, but is oddly silent about 4130 tube for 3,500-lb cars (which is the high-water mark; Unfair better not weigh more than that). It does allow for 1 3/4 tube and .120 wall for DOM (mild steel) tube. After much consideration and a consult with some NASA rules officials --which really didn’t help-- we decided to use 1 3/4x.095 4130 tube.

[RADustin]

awesome! exactly what I was looking for. My idea was to get a prebent cage in whatever size/material tube I want and just "finish" it. I have the required tools but the time savings is usually well worth it for someone else to get me 80% of the way there.

I'm keeping a bolt on front subframe so I need to figure out how I want to tie the upper supports from the sub into the cage(dash bar).

Other than that I think I have a real good idea of what I want.

Thanks!

[Ron Sutton]

I went down that road a while back. Here's what I did:

http://www.superchevy.com/technical/chassis/frame/sucp_1106_chevrolet_camaro_custom_roll_cage_instal lation/

An excerpt:

Speaking of books, the first thing to decide about the cage is the proper diameter and wall thickness of the tube itself. The NHRA requires 1 5/8-inch tube with .083 walls for 4130. NASA’s rulebook has a whole section on tubes and wall thickness, but is oddly silent about 4130 tube for 3,500-lb cars (which is the high-water mark; Unfair better not weigh more than that). It does allow for 1 3/4 tube and .120 wall for DOM (mild steel) tube. After much consideration and a consult with some NASA rules officials --which really didn’t help-- we decided to use 1 3/4x.095 4130 tube.

That's exactly what my main cage is built from ... 1-3/4"x.095" 4130. It meets or exceeds all rule books ... except off road truck racing. :yeah: