Just to give an idea on diesel torque 3series 3.0 335d gives 428lb ft @ 1750-2250rpm versus 4.0 V8 M3 giving 295lb ft @ 3900rpm plus diesel does combined 42.2mpg as opposed to 25.2mpg for M3 and then there is car tax diesel is £250 first year then £180, M3 is £950 first year then £435. So think a diesel M3 could eventually happen lol