The front suspension is the same as a TJ and ZJ, so a lot of parts from those Jeeps will work in an XJ. A TJ coil spring will yield a bit less lift in an XJ because the drivetrain is further forward in an XJ than a TJ. However, a V-8 ZJ Grand Cherokee spring will yield about 1-inch lift in an XJ, but with no fender trimming, you will need about 6 inches of lift just to clear 33-inch tires. The control arms are good to about 3 or 4 inches of lift. After that, the angle at rest is too great and will lead to poor handling and ride characteristics. At that lift height you will either need drop brackets or long arms to get the ride and articulation you want. Shown are Rubicon Express drop brackets.