The textbook answer is that a static rollover will happen when your center of gravity is no longer supported (i.e. when there isn't a wheel undeneath it). A dynamic rollover is easier to "accomplish", for it has to do with momentum (mass times velocity) and thus harder to calculate.
Any four wheeled vehicle will need to locate it's center of gravity inside the wheelbase, but I would
guess, given the monstrous gas-guzzling engines we own, that the CG is slightly forward of the wheelbase's midline, slightly left of the wheelbase centerline, and, heightwise, somewhere between the chassis and the engine's midline (give or take a few inches). Of course, the CG moves as you empty the gas tank, load the roof rack, attach a winch or recovery point, etc.
In my Disco, I estimate that the CG is in the center console, between the the two front seats. Let's call it right underneath where my window switches are. Statically, if this magical point is outside the wheelbase, I'm rolling over.
Looking at a profile picture of the Disco, I'm guesstimating a rear/forward static rollover at angles geater than 60 degrees, and a sideways static rollover at angles greater than about 45 degrees: both well over 10 on the pucker factor scale (at 10, a piece of carbon comes out a diamond
), and clearly 5 points on the scale greater than anything I've ever done. And, as mentioned by a few already, well into unknown systems-performance parameters (e.g. fuel, oil starvation).
In the pictures Mike posted, the Disco is at about 80 degrees (hard to tell exactly as slopes are impossible to really see from small frames) and has not rolled. Mind you, the pivot point is no longer the wheel, but the bumper, but you get the idea.
I would not recommend testing those parameters out.
NB: dynamic rollover is a totally different story (i.e. it takes much less of an angle to roll), as not only is there an energy factor (as previously mentioned), but also suspension, tires, driver skill-level, etc. come into play.
Those of you who do that kind of extreme stuff, how far have you gotten?
