When BMW lowered the M3 by 10mm (0.4") for Japan they changed the struts and the springs (but not the bumpstops or the guide support). Actually, until I read this thread, I thought that all Dinan had done was bring the Japanese market components to North America and match them up with their special springs.
Reducing the height of the bump stop risks damaging the valving inside the damper. I guess it doesn't happen, otherwise Dinan wouldn't do it.
If you tell REALOEM that you've got a European car, it will give you the part number for the Japanese struts.
Last edited by JAJ; 09-14-2009 at 12:30 AM.