full frame under XJ

There's a guy around here that did it, looks like complete dogsnot. About the only thing that I've thought of doing that's close to that is cutting off the framerails (leave about 2" of them) and build a new frame, weld it in. Basically building stouter framerails is all that is though.
 
I think, instead of trying to throw the XJ onto an existing frame, you might want to strip it down cut the rails out and weld in some 4x4x3/16 box tube, or 3x6 or whatever you feel like.
Or use the existing rails as a starting place and add boxing, making the effective rail structure wider.
Or plate the things on three sides.
Etc.

There are other ways to get frame-built durability out of the xj - no need to ghetto rig one onto the other. The fab involved in doing it well is probably no less than it takes to reinforce an XJ and keep it looking / working well.
 
hey I like MURDERED OUT's project, yes the sch 40 cage is dumb, other than that i subscribed i want to see how it turns out. People on here are a$$ holes sometimes. Don't let it get to you.... keep it up I can't wait to see your next step.
 
Looking for ideas on this as well, and found this thread.

As for looking like complete crap, this is not an XJ but a Comanche, and I think it looks pretty good....wish I could find details on it. :banghead:

370702034.jpg
 
Looking for ideas on this as well, and found this thread.

As for looking like complete crap, this is not an XJ but a Comanche, and I think it looks pretty good....wish I could find details on it. :banghead:

370702034.jpg

That actually looks decent, like he took the time and effort to figure out how to mount the unibody in a way that sits down nice and low. I'd be interested in seeing how he did the mounts. I'm sure it was an ass-load of work.
 
Somebody that was in my Jeep club has a XJ on a Scout II frame. He claimed that the unibody frame rails line right up with the Scout frame rails. The guy only came to a couple of meetings and I only saw photographs of it that he brought with him. It was about a year and a half ago and thats all the details I can remember.
 
I think, instead of trying to throw the XJ onto an existing frame, you might want to strip it down cut the rails out and weld in some 4x4x3/16 box tube, or 3x6 or whatever you feel like.

FWIW, I am planning on doing this for my XJ (I think the OP should not do it, I want to be one of the first :laugh:). I just need to finish shopping for a house so I have a garage or yard to work in where I can leave my "mess" out for a week or 2 while I work. :D

I measured mine and I am pretty sure the stock XJ unibody rails are 3.5x3.5". I planned on building a frame out of 3.5x3.5x1/4" (or maybe x3/16"). That measurement was made directly below the passenger seat floor pans since my floors are completely cut out right now. The unibody does widen out to maybe 3x6 where the front control arm mounts are I believe, however that extra width may have been for the UCA bracket or something. I didn't really look into it TOO much. I drew out my plans based on full 3.5" box (using long arms for the front suspension).

This project is kind-of hinging on the fact that I get my floor pans replaced and deem the Jeep to be worth throwing more money into. I think it will be, but I will have to wait and find out for sure :D
 
FWIW, I am planning on doing this for my XJ (I think the OP should not do it, I want to be one of the first :laugh:). I just need to finish shopping for a house so I have a garage or yard to work in where I can leave my "mess" out for a week or 2 while I work. :D

I measured mine and I am pretty sure the stock XJ unibody rails are 3.5x3.5". I planned on building a frame out of 3.5x3.5x1/4" (or maybe x3/16"). That measurement was made directly below the passenger seat floor pans since my floors are completely cut out right now. The unibody does widen out to maybe 3x6 where the front control arm mounts are I believe, however that extra width may have been for the UCA bracket or something. I didn't really look into it TOO much. I drew out my plans based on full 3.5" box (using long arms for the front suspension).

This project is kind-of hinging on the fact that I get my floor pans replaced and deem the Jeep to be worth throwing more money into. I think it will be, but I will have to wait and find out for sure :D

Well, figure out the cost of materials for floor pans and frame rails and welding supplies. If that number is less than a new (awesome, off roadable) station wagon... then go for it.
I mean, what else are you up to?
 
edit:posted in wrong thread.
 
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Well, figure out the cost of materials for floor pans and frame rails and welding supplies. If that number is less than a new (awesome, off roadable) station wagon... then go for it.
I mean, what else are you up to?

I already have the sheet metal and welding equipment to do the floor pans, just a matter of finding the time to do the work.

Frame rails, if done with all 3.5"x3.5"x1/4" I think came out to somewhere around $4-$5 per foot (I want to say $5.90 per foot, but it may have been 4.90... I called about the price a month ago and don't have it written down anymore). So I figure it will cost $200 for the necesary 3.5"x3.5", any other C channel to box in the areas that need even more strength may add a bit to that. Again, still haven't completely measured all the angles and unibody dimensions, still have to work out the details.

I would also probably end up picking up a 220v welder since all I have is a miller 135 which is rated to 3/16". Granted I COULD use 3/16" thick box and technically be within spec of my welder, but I would rather do it right and use a 220v. That or just buy a friend a 30 of beer or bottle of scotch and have him swing by for a wkend. He is easily one of the best welders I know (welder by profession) so I would trust him welding up a frame.

Either way, it could be done for a reasonable price and would be a fun project. Hell, even if it didn't work out in the end and I needed to junk the XJ I could just buy another rusted out XJ and swap my current lift/tires/etc over.
 
Looking for ideas on this as well, and found this thread.

As for looking like complete crap, this is not an XJ but a Comanche, and I think it looks pretty good....wish I could find details on it. :banghead:

370702034.jpg

I seen this at the Silver Lake Dunes its done really nice. I also seen some wild LS1 XJ's
 
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