Rollbar improvement for strength & originality

[mickmate]

Just put some pics up here csxinfo.net - csxinfo Forum

[Clayboy]

Nick,
That is a great idea, have you figured out a version for SPF's or just CCX's and CSX's?
I would be interested in one and I'm sure others would be also.
Bob

[rdprice]

Geez Nick...are you ok?
DETAILS?

[mickmate]

All you need is a measurement between the back of the tube and the firewall where it has framework behind it. You also want to check the angle or parallel between them. Lots more details and graphic pictures on the link. Those with weak dispositions should not follow it, you have been warned!

[mickmate]

Geez Nick...are you ok?
DETAILS?

This happened at the hands of the original owner. He survived luckily but only because he didn't have shoulder straps on holding him up in harms way. It is better than it ever was now.

[D-CEL]

Hey Nick,

That is a fantastic idea!

Best regards

Jason

[bret a ewing]

If you are interested, there is also a bolt-in horizontal spreader bar between the rollbar uprights that also provides mounting eyelets for shoulder straps. I would think the bar would add some structural rigidity.

[TimG427]

I thought I knew lots about these cars, but I never knew this bracket existed until I saw the CSX car I purchased. It had this bracket on it and I thought it was incorrect. It's still on the car.

[D-CEL]

Hey Nick,

I like this mod and Im going to do a version on my car. However, the cross bar on the SPF is square tube. I will drill thru and bolt it in.
But that got me thinking about the flat plate on the round tube of the CSX.
I think it must be gusseted and welded like a spring perch.
I feel that in and impact like the one on csxinfo.net, the flat plate would deform around the tube sufficiently to loosen the clamping force and slide laterally, allowing the hoop to partially collapse and exposing the driver significantly.
I think it must be welded in to be truely effective.



Best regards
Jason

[Cobra #3170]

I cringe when I see chrome roll bars, and wonder if the user had a dehydrogenation heat treat done after the plating process.

[D-CEL]

Hey Bruce,

I wouldn’t worry too much about that. Typically, hydrogen embitterment relief is only addressed on high strength materials with a min tensile of 150ksi min.
Even if normalized 4130 tubing was used, it would be well below the strength threshold (about 110 ksi…as long as the bar was not heat treated after forming….)
I doubt anyone who would have a bar fabbed out of “N” 4130 would have it chromed. At least I would hope not!
I would really be concerned about the lack of ductility in the welded area if “N” tubing is used for this application.

I hope you and my favorite Cobra are doing well.

Best regards
JASON

[mickmate]

Hi Jason, the originals had square tube behind the bulkhead. I can see your point but I really believe they will help support the roll bars if needed. Just tying in that third anchor point for that long slender tube makes a huge difference to its rigidity. With a carpeted piece of fiberglass between them there's no way you're going to stop it slipping unless they are mechanically connected. I wouldn't want to mechanically connect them like they have been on the rear brace. They simply drill holes through the thin wall frame tube to weaken it in the rear brace mount area then they crush the tubes with the bolts through it. I use heavier wall tube, oversize the hole then weld in a sleeve. Now you have something stronger than it was as well as a crush prevention.