Well yes and no......
Its even harder to find out how much of a drop a car will have on the EXACT same setup. I have Ireland Stage II springs and Bilstein Sports....Its lower than ALOT of peoples cars with the EXACT same setup. So the thing is these cars can vary alot. From old parts, bent parts, etc....so its a tough thing to say definitively what will work on one car and what will not work on another. There is some experimentation that goes into it all.