On the coil side of the equation, springs from a V-8 equipped Grand Cherokee ('93-'98) will give about 1-inch of lift to a six-cylinder-equipped TJ, XJ, MJ, or ZJ. If your MJ or XJ has 2WD springs in it you can expect more like 2-3 inches of lift. Likewise, using six-cylinder springs in a four-banger will yield about 1-inch of lift while the V-8 springs will be just north of 2 inches. Of course, all these measurements depend on how beat your stock springs are, how much of a porker your Jeep is, and the condition of the donor springs.