[JoosyJoos]

It's pretty smart of M to launch the new engine in the X3 M for a while as real world testing. That way before the M3 is launched they can iron out problems with the engine--- plenty of 2001 E46 owners would have been happy about that if it had happened lol.

To all who say that putting it in the X3 M is a big mistake and that they shouldn't recycle the same engine for the M3... I think the mistake you're making is assuming that there won't be any upgraded parts which if its similar to how the M5's S63 is being treated is patently false. Its clear that M has taken the time to tweak the S63 for the M5 with larger intercoolers etc. I would even expect different cams ultimtately. An M3 doesn't weigh nearly as much as the SAV so it wouldn't need as much torque down low (higher cam profiles).