The torsion bars don't settle but the front end will depending on how you bolted it together. The correct process is to put the front bushings together snug on the lift and then torque them down at ride height. If you torque stuff together while the car is on the lift (common mistake) then the car will slowly settle over time as the weight of the car twists the bushings. If you put the car together correctly then it should hold the ride height after you drop it on the ground.