they say about 10-15mm, i fitted to my G40, but due to my increased castor angle with my subframe, the lowered caps were rubbing the front edge at the top of the inner wing where the mounts are.
So I'm back running stanadard hieght eibachs now, and I feel that the extra 10-15mm drop did give the car more front end grip and better traction, so cutting was in the back of my mind, but wouldn't advise it as not done it myself and wouldn't want you to wreck a set of springs on my say so. Though i gotta say that when loaded the bottom 2/3coils on the eibachs are resting on each other anyway, so from that perspective cutting 1 off would drop you about 8mm and 'probably'
not effect the spring operation at all.
Comments/thought's??