need help with roll bar dimensions

[Vette 76]

Well, I am at the stage of building a roll bar in my 72 454 vert. rebuild. Was wondering what thickness and diameter tubing is adequate. I do quite abit of welding with my business so the install is not a problem. I am concerned about adding weight but want to get it strong enough. Also, where is a good place to get a professional looking bend for the part that will go above my seats. Any ideas out there? Again, Thanks so much Vette 76

 

[Tom Bryant]

Roll bars

I don't have the direct answer for this but it depends on where you want to race. SCCA, NCCC, NHRA ect. all have minimum specifications for roll bar materials and what certifications they require for the welder/builder. Even if you aren't planning on sanctioned competition building to the required specs is a good idea.

Tom

Tom

 

[Ol Blue]

roll bar dimensions

vette 76
When rebuilding my cousins ex-IMSA 68 Corvette I cut his roll bar out and had a new cage complete with NASCAR door bars put in it. I used 4160 chrome moly. I can't remember what the military spec was though. It was 1 3/4 inch with .125 wall. I think the SCCA only required .090 wall, but I'll take the extra strength for safety, even with the extra weight. Hard to believe they approved that old roll bar back then.

I looked into an Autopower kit, but I wanted better door bars and had the entire cage fit to the car.

I think you could get just a roll bar kit from autopower. I saw a kit in a Miata and it was very nice.
Good luck
Ol Blue

 

[69MyWay]

You need to go to www.tropiczoneracing.com (that is TZracer here on CAC), click on the race car to enter the site. You will see his Street Vette link. He just finished having a roll cage built and welded into his 71 454 coupe. It is the real deal, less the door section.

You can contact him for more details.

 

[Tom Bryant]

Very impressive as is the whole site. How is the '71 project coming aong?

Tom

 

[racecar]

1 3/4 x .095W DOM tube is the spec for SCCA V-8 road race cars. The DOM
(drawn over mandrel) tube is harder and stronger than ERW (welded) tube. If you use welded tube for SCCA, it has to be .125. That is some heavy stuff.
.125 DOM or .125 4130 (moly) is super strong stuff if you can afford the extra weight. 4130 is more difficult to weld, it can become brittle. For a big block, speeds of 150mph, 3000 pound car, maybe the heavier tube would be a good idea. Some of the vintage cars use 2" tube for the main hoop. It looks pretty beefy, but space is usually a premium in a Corvette.
Good luck!!

 

[69MyWay]

Very impressive as is the whole site. How is the '71 project coming aong?

Tom

Let's just say you will be seeing a whole lot more of this car in the near future since it is coming to stay with me until I can get the nose and front fender flares on as well as other stuff.

 

[Tom Bryant]

:cool Aren't house guests fun?

 

[69MyWay]

:cool Aren't house guests fun?

This is the ultimate house guest. You can lock it in the garage, cover it in dust, and leave it in the dark.....and it does not complain!

 

[427SB]

You need to check out www.dragvette.com. He sells a rollbar that looks like a supurb job for around $200.

 

[427SB]

I just checked and he doesn't have any listed right now. He is really nice and helpful; drop him an email.