Hi, I have a diesel Audi A3 1.9tdi (2002). I have put a set of 18 inch rs6 wheels on the car and am looking at upgrading the suspension. The ride is slightly harsher with the 18 inch wheels as i was on 15 inch wheels. I want to lower the suspension but i do not want the ride to become too harsh and bumpy. Do you guys think with 40mm it will become too bumpy? Does it depend on the quality of the springs, if so which ones are best to go for? And does it make a difference if i change just the springs, the whole suspension or get coilovers?? Any help would be greatly appreciated. Thanks.