As usual when dealing with a specific issue on a specific vehicle, it will sure help to know make, model, year, since then it's more likely for you to find someone who has dealt with the same issue.
The mention of torsion bars implies that whatever the vehicle is, most likely uses a double-A-arm front suspension of some sort.
Small changes in ride height will likely remain within the bounds of maintaining acceptable suspension geometry and constant-velocity joint angles. But small changes in ride height probably won't do much to address the ground clearance issue that you seem to have.
Large changes in ride height will require some sort of re-engineering of the suspension, steering, and drive line. I've seen subframes built that essentially move all of the suspension attachment points and the front diff down relative to the frame and change the angle or position of the diff to minimize the bad side-effects on the front drive shafts. There will be an unavoidable rise in the center of gravity of the vehicle (it'll be more prone to roll-over).
If it is a road vehicle, raising it up will raise the height of the bumpers (lethal to other vehicles in a collision - and don't forget that raised center of gravity that makes it more lethal to you, too), the height of the headlights (you'll be "that guy" blinding others at night), etc., and in some areas (including mine) it may make the vehicle uninsurable or illegal for road use. Of course, if this is an off-road vehicle, none of this matters.
