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vbjornsson
September 30th, 2003, 20:54
I was just wondering what you guys do to strengthen the unibody for the xj. Is there a way to tell if a unibody is bent or out of shape?

Thanks for your help.
Eagle
September 30th, 2003, 22:33
Originally posted by vbjornsson
I was just wondering what you guys do to strengthen the unibody for the xj. Is there a way to tell if a unibody is bent or out of shape?

Thanks for your help.

A good roll cage should attach to the "frame" is several places, and be triangulated. That's the best way to stiffen the chassis, if you can accept the inconvenience of several miles of tubing ( :) ) in your passenger/cargo compartment.

As for knowing if it;s straight, body shops have books that give a zillion measurements from point 'A' to point 'B,' point 'J' to point 'Y,' etc. They check 'em all and if they don't match what the book says, they know something is tweaked.

"The" factory service manual for the 1988 was actually several different books, one of which covers just the unibody (plus doors). It has all those domensions. I haven't looked in a newer FSM to see if the all-in-one books include that information, or if it's a separate publication just for body shops.
mmyers
September 30th, 2003, 23:58
Originally posted by Eagle
A good roll cage should attach to the "frame" is several places, and be triangulated. That's the best way to stiffen the chassis, if you can accept the inconvenience of several miles of tubing ( :) ) in your passenger/cargo compartment.



Like this???

http://img.villagephotos.com/p/2003-9/371723/08230044.JPG
Eagle
October 1st, 2003, 00:09
Originally posted by mmyers
Like this???

Well, sort of -- but with a roof.
mmyers
October 1st, 2003, 00:41
Roofs are for XXXXXXs!! J/K

Golf umbrellas rule!!

M.
jpnut2
October 1st, 2003, 10:34
in an earlier post someone said that a sunroof took away from the structure.
I bet yours flexes like crazy:roflmao:
dave
October 1st, 2003, 11:08
i want to see pics of " roll testing " that jungle gym!
jeep.xj.4x4
October 1st, 2003, 11:57
That rollcage is bad a$$!
giranger
October 1st, 2003, 14:42
The pic doesnt work. Can someone post it up again:D
JEONLYEP
October 1st, 2003, 15:33
Please let me see the picure too!......
mikedashg
October 2nd, 2003, 05:15
Everyone always talks about stiffening the chasis with this and that, but what about TOO stiff? The unibody was design to flex a little, especially when wheeling and you have the force of the axles going in different directions when they articulate.

A good point was brought up by someone about how those steering box braces that go frame rail to frame rail. I would think that would be a bad thing because the frame rails are flexing and you've got this rigid thing inbetween which also is attached to your steering box. Sounds like a disaster waiting to happen. Unless I'm making a mt out of a mole hill?

And what about those guys with the huge subframes, and boxed uniframes and tubes going all over the place. Wouldn't that crack the unibody real easy if you flexed the thing up over and over again?
KarmirXJ
October 2nd, 2003, 05:27
ok... explain to me how its going to crack the unibody if its stiff as hell...

the only reason it cracks is bending and twisting over time... think of a paper clip, you bend it too many times back and forth eventually its gonna give. same thing with the unibody... now if you make the unibody stiff as a purv's wang:D then you have nothing to worry about. all you gotta do is just triangulate everything. maske sure theres no loos ends. :D