Just recently bought a set of lightly used Bilstein coilovers from a 2013 GP2 for my 2011 R56S, and noticed there are no bump stops on the fronts. Is this normal? Do the Bilsteins not need bump stops? I have not looked at the rears yet to see if they have bump stops. Obviously, I cannot use the bump stops from my stock front struts on these, as the shaft diameter is so freaking huge on the Bilsteins. Anyone?

 

Front struts for the GP2 are inverted and do not have external bump stops. So, nothing needed there.
http://www.realoem.com/bmw/enUS/show...diagId=31_1024


The rears will use shorter bump stops:
https://www.ecstuning.com/b-genuine-...r/33536863754/

http://www.realoem.com/bmw/enUS/show...diagId=33_1704

 

How much lower is the GP2 suspension in comparison to the stock MCS? (2007)

 

The GP2 suspension is adjustable, so... I think I've seen the GP2 to be 1/2" lower than MCS at max height.