Gary Z

When installing a roll bar in an F-body, the main hoop is usually welded to a 0.125 inch thick 6 by 6 plate that is in turn welded to the 0.030 thin floor. I have discovered that the rear subframes are below the spots where the plates are usually located but there is a significant gap between the floor and the top of the subframe. I'm thinking it might be better to puncture the floor and weld the hoop directly to the subframe? Has anyone here done this?

Gary Z

Or better yet, cut an X in the floor and fold the corners up and away to expose the subframe. Then weld the plate to the subframe. Trim the floor corners leaving enough material to bend it down and the weld the floor to the plate. Could be neat and strong. What say you chassis guys?

9sec93

iTrader: (67)

i have done something similar to this. i cut the a hole in the floor and welded the main hoop directly to the subframe connector. then i used the 6x6 plate cut in two pieces and notched it around the bar. then welded the plate around the main hoop and to the floor to cover the hole and tie the main hoop in to the floor as well. this was a friends car but gives a good example.


you could also weld a bar from the door bar down throught the floor to the subframe connector. i did this in my camaro

9sec93

iTrader: (67)

i see what you are saying now. i didnt see the pic until just now. that is how i did my camaro. the floor was cut out like the pic you have there. welded 1/8" plate on top of the lca mount and then put the main hoop to it. i read subframe in your post and thought you were talking about subframe connectors. either way it will work fine. you could never make it too strong.

RARON455

iTrader: (35)

Only question I have is what are you using to make up the difference in Height, If you go thru the floor I would imagine that you lose at least a half inch on main hoop height. I have my jig notched wolfe cage in the garage and havent gotten around to install yet, I do like the idea of the bar welding to my SFCs instead of the sheet metal on the floor.

Gary Z

The main hoop of my S&W kit has a little extra length and would need to be trimmed to clear the headliner if the plates were welded to the floor.

JL ws-6

iTrader: (50)

You'd need the main hoop bent with enough material (height) to go to the frame connector.

It's not a bad idea going to the frame connector, if you have chromoly ones, that are the right diameter (I'd just do 1.75 inch dia tubing for this in this case) and connected the main hoop to them, you'd be able to use the frame connectors for part of a 25.x cert too as well, have to check the rule book on that, but I think it would be legal.

Not a bad idea. Doing the Wolfe thru the floor frame connectors, and building off of them also would probably be legal for a 25.x and would make for a good rigid chassis as well. Someday, when I redo mine to a 25.x I will probably cut the entire cage out, start from scratch (painful in the $ department, but to be done as light and strong as possible it would be the right way) and do the thru the floor frame connectors, or at least build a set from chromoly, and build the cage up off of that.

Gary Z

Thanks for the feedback and the pictures.

Gary Z

JL, thanks for your suggestions. I was unaware of the Wolfe subframe connectors. Wolfe has some very helpful pictures on their website. I don't think I'll do anything that radical but they are a good example of the approach I want to take.

tee-boy

iTrader: (8)

Burkhart sells a set of CM SFC's. Don't know the pipe diameter.
Would make a nice clean weld to the CM cage.

sweetbmxrider

iTrader: (13)

i was discussing this with my builder and had a similar thought coming off the subframe connector to the main hoop. good ideas here though thanks for sharing.

9sec93

iTrader: (67)

that is the same stuff i have used in all my cars. it does come long so you can cut it to the length you want. the notches fit like crap so you have to re notch everything but the main hoop fits nice and the price is right.

y2k_ta

iTrader: (80)

Agreed. That's the same kit I used. The one thing that turned me off of the Wolfe kit was the lack of height on the main hoop. Every car I've seen with one installed just doesn't look good to me. I like having the bars tucked up out of sight as much as possible.

malibu1979

That is how I am doing mine. You can see pics here.

https://ls1tech.com/forums/drag-raci...o-project.html