You can\'t drop a car with shocks. Only springs. That being said, shortening my strut housing did lower the car 1.5\", but the ride height is adjustable with the Ground Control threaded collars. The car is probably dropped a good 3 inches from stock. There is pretty much no gap between my front wheel opening and the top of my front tire (205/60/15). The rear is close to the same.
Shortening the front strut housings allowed me to run a shorter strut, which in turn, allowed me to lower the heck out of the car and still have good suspension travel. My setup is not for the faint of heart. It is a very stiff setup, which is why I run 60 series tires on the street, so that they can soak up some of the bumps.