i thought about taking the doors off, i'd love to make some soft doors for it. wish it was a 2 door.....
how bad does that thing flex with the doors off? gotta think it loses a bit of integrity.
Think through that for a minute....... doors vs. no doors.....
If the door provided any sort of integrity to the unibody for overall strength, then during moderate to severe suspension flexing...... you'd have to expect that the doors would NOT open..... they'd be in a bind with the door sills providing rigidity for the unibody. Right?
The only thing the doors would be important for regarding integrity would be for crash/impact integrity. The door acts as a brace for the opening when closed.
I had a pretty rusty and well 'wheeled '84 XJ and yes, the doors did bind when severely flexed. Haven't had that issue with the '93, '95, '96 and '97 rigs I've owned and wheeled..... but you can feel the unibody move a bit when off road if you put your fingers over the gap between the top of the door frame and the roof/rain gutter area when 'wheeling.... you'll feel the gap get wider/closer. The '93 and the '97 both got frame stiffeners and cages which almost eliminated that door/roof gap movement.
The more a person 'wheels their rig with out doors I suppose certainly could help contribute to unibody cracking and flex - cutting off roof sections and removing pinch seamed areas will contribute to this - so we XJ folks generally advocate a well anchored cage for both occupant protection and unibody support.
If you do some image googling I think you'd find that the XJ's will do "ok" in a very light, low speed side rollover, but generally don't survive it to 'wheel again without alot of bending/straightening/fixing. Side flops are mostly all about what they flopped onto. Mine caused quite a bit of damage simply due to the nature of the obstacle:
My old '84...... this kind of flexing would generally render the doors stuck shut. No sliders, no stiffeners, no cage....... lots of rust though.