Originally Posted by propr'one
although i respect your opinion, the e30 m3 is an e30, which is the designation for a model of 3 series. ditto for all other m3's.
I have to disagree with you here. Z1 is also E30 and Z3 is E36, I'm sure you would agree with me that those cars are part of the Z series.
Historically speaking, M cars became an M series sometime in 1999. Before 1999 all M cars were listed in the number series category. The separation is obviously for the marketing reasons.