Building roll cage for 2005 Ford GT - any tips on joining mounting points to aluminum frame?

[Jim]

I am in the process of building a FIA/NASA approved roll cage in a 2005 Ford GT and the rules don't address attachment strategies/requirements for attachment of the mounting points to the aluminum structures. The rules provide guidance for mounting plates (0.120" thickness minimum) size and how they are welded/bolted to steel floors/sills but in this case, I'll have to either add alum "bolt to" plates, reinforcing plates, and/or backup plates to the structure. Wondering if anyone has explorer/researched this and what their findings were. Yes, I have the rule books and I can "interpret" intent but input would be appreciated. I have the MaTech GT build photos/specs and insight on how they did it..... but I can see it would not meet NASA minimum standards (e.g. 18 in2 minimum size for mounting plate area on floor corners).

 

[gtjoey]

Jim don't hold me to it but if you pull up the flooring the earlier cars at the time had dimples for locating a roll bar.
If you cant get Rich Brooks at the GTGUYS . H would be the best from ROBERTSONS racing who built the car which came in 3rd at LeMans
Good luck PM me if you need H number.
gtjo0ey1314

 

[thegtguy]

Hi Jim,

Feel free to drop by and check out the Workhorse #5 I have here. You can see how Ford directed us to build the cage for all of the test cars. I have seen a few other "cages" over the years and they would have been better off not having anything there. One of them was bolted to the floor pan and that is completely useless.
Best method is to make a "C" over the side extrusion then nut and bolt it after crush sleeves are installed into the sill. This is how Tom Reichenbach directed us to build them.

 

[Jim]

Thanks Rich - that would be super helpful. I will call first but need to get over there to visit soon.

 

[Specracer]

^^^ Damn Jim, your shop looks like a living room. Quite nice