Quote Originally Posted by lawtonglenn View Post
perhaps the BMWs lose less than the average 15% in the drivetrain?

here is a link from a guy who was surprised to find only 10% loss in his stock E46 M3:
Could be an optimistic dyno, but I believe the real culprit is that BMW understates the stock numbers. I've heard that it might be because of insurance rates in Europe. No one complains when they get more power than stated, for the other case just ask Mazda...

Either way the 30% gain the ITAC uses takes that into account, and was back-calculated from whp numbers using the 15% loss assumption.

Assuming 15% driveline loss, a 323 at 210whp is making 145% of the published stock power.