Cage design thoughts?

[Chickntrk]

Looking for thoughts and opinions here mostly....

I'm working on building a simple rollcage for my 78 K20, I want to use the halo and front down bars from the Diy4x kit but Id like to tie my B pillar main hoop to the back half with two down bars through the back of the cab above the rear window. This is where my concern is....I was going to run those downbars to the frame near the front spring hangars but Im worried that with the front half of the cage tied to the cab and those bars welded to the frame Ill create an uneven distribution when the frame tries to twist. I thought about tying my B hoop to the frame as well but then I have rigid mounting at the B pillar and rear but nothing forward of that so again with frame flex its unevenly distributed.

I want to do something similar to this:


So for any of you that have done something similar did you run your rear bars to the frame? Plates in the bed?

Another thought I had was to just use Kerts cage in the cab and build something similar to this in the bed area only since the bed is already rigid mounted to the frame. Maybe I'm overthinking this...

 

[nvrenuf]

There's a guy that goes to Fullsize Invasion (not sure about BB) that's on Instagram, "solitary_motorsports", he's got something similar to your description.

 

[Bent77]

Do you have a Bender or welder?

Anything is better than nothing, but not doing crazy also helps. Where are you going to put it where you will have to have it?

 

[Chickntrk]

Yes! That’s what I’m thinking….I sent him a message, thank you!

 

[Chickntrk]

Do you have a Bender or welder?

Anything is better than nothing, but not doing crazy also helps. Where are you going to put it where you will have to have it?

I have a welder, I have access to a bender, I’ve done cage work with my buddies that have circle track cars and on a few Jeep XJs but they are all unibody or else a cage chassis..on the unibody’s it’s all flex’s together so I guess this is my first hybrid where I wanted the cab to just be bolted with floor plates but I’m not sure if the rear bars can be rigid or if that will want to rip the cab apart?

 

[folkenheath]

You are correct in the fact that some rigid and some soft mounted is not the correct way to do it. You could install solid aluminum body mounts, then do what to you are saying. Or keep the roll bar in the bed since the bed is rigid anyway. If you put the roll bar in the cab and leave the cab soft mounted, brace it to the frame with poly mounts or something, just make sure it is strong enough whatever method you decide.

 

[Chickntrk]

You are correct in the fact that some rigid and some soft mounted is not the correct way to do it. You could install solid aluminum body mounts, then do what to you are saying. Or keep the roll bar in the bed since the bed is rigid anyway. If you put the roll bar in the cab and leave the cab soft mounted, brace it to the frame with poly mounts or something, just make sure it is strong enough whatever method you decide.

I’m not sure I’m ready to commit to a solid mounted cab yet only because the truck still sees some street time, although with the ride and noise I doubt it would make much difference…I think I’m going to do a hoop on the bed behind the cab with kickers to the frame, and mount my down tubes solid to the frame and maybe do an x brace between the down bars.