I've never tried to crank up a 2WD, but I'd guess you could get at least as much as a 4x4 if not more. (Less worry about binding in the drivetrain) To get an idea of what you can get, measure from the center on the hub to the fender lip, then jack up that side from the frame leaving the tire to droop, measure again and you will get your absolute limit for gains. Full droop would be a bit too much, since it would be a rough ride and harder to align, so knock off about a half inch to an inch.
If you put the springs over the axle (SOA) in the rear and crank the front up as much as possible, I'm thinking you will be about an inch or two low in the front. SOA in the rear is almost 6 inches, the width of the axle plus the thickness of the spring pack. You might squeeze 4 inches out of the torsion bar crank in the front, but like I said the 2WD may lift easier/more than the 4x4.
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95 Isuzu Trooper Daily Driver
86 Isuzu Trooper reliable backup
77 LUV 2wd stock beltway blaster (resting)
79 4x4 LUV project: 2.6L, 5spd, 31s (eventually)
MEPR: Man, my 4x4 makes all other LUVs look good
