BMW’s motorsport division is testing a brand-new version of the M2 with a four-pot engine, unlike its road-going cousin. Could it be the best yet?

BMW has announced a range of powertrain updates ... Moving up to the twin-turbo 40d version of the same engine above, which is offered as the 740d, the X3 M40d, and X7 xDrive40d (all not currently ...