More like 5-6" in an SOA. You need to measure the thickness of the spring pack at the spring pad minus the thickness of the main leaf and measure the distance from the bottom of the existing spring pad to about 1" above the axle tube and add the two measurements. That will give you a pretty close measurment in lift.

The only way you'll only get 3-4" of lift out of a SOA is if you're working with a 2" axle tube, a leaf pack that consists of two leafs or you're welding the springs directly to the tube. Or 'D' - "All of the above." <img src="/forums/images/graemlins/smile.gif" alt="" />

IMHO, before I worried about what a SOA would affect I'd figure out how I was going to lift the front the same distance first.

Edward