until tomorrow i can not give you an exact answer, but tomorrow iwill go outside and measure the stock ride height of my old 318 (put stock back on) my girlfriends 325 and my dads m3 all of which ride on stock suspension. i will also take measurements on my lowered 325 and get back to you as for now heres some car off autotrader.. has 17inch wheels but looks like it is on the stock suspension
heres my car
in this pic you can see the back of the m3 my car my girfriends 325 and my moms 328... of this is on gravel with weird dips etc... so its not very accurate
David