Originally Posted by MrFatbooty
There is really only one way to maintain proper suspension travel when lowering and it can be accomplished through two methods. The lower shock mount has to be shortened. The full length of the shock is not taken up by the shock absorber itself, so shortening the mount makes the overall length of the shock less, to match the lowering. This can either be accomplished with shortened shocks (i.e. Neuspeed/Koni SP3) or with a full coilover setup that has a threaded lower mount that lets you change the ride height while keeping the overall length of the shock/spring combo the same.
the other way to do this is to extend the upper shock mount upward with a kit like Ground Control's upper mount. It basically bolts to the top of the strut/spring assembly, and raises the upper shock mount a little less than 2 inches, thus increasing travel by that same amount. This same approach can be done DIY if you're a decent welder (at least in the front)... simply extend the upper shock mount as far as hood clearance will allow.