What engine size is your car?? For my old 1.4
Ibiza I bought a -40mm lowering kit but found out it was for a GTI. Anyways I fitted it and the car sat quite nicely at the back but the front was only lowered by about 20mm. Found out it was because the front springs were really stiff (to cope with the 2.0 engine), but because mine was a light 1.4 engine, the front springs didn't get compressed enough. OK not a great pic, but you can still see that the front ended up being a lot higher than the back
Mig