Originally Posted by JustinTJ
Probably because it starts with more.
On a side note, the 328 tune brings it up to 335 power levels. Wonder if it's more cost effective to tune or just buy the upgraded engine?
The BMW N55 is underrated in the 335i, and makes around 270rwhp stock. That's closer to 320hp at the crank, yet BMW rates it at 300hp at the crank.
My gut tells me the N55 in the 640i/740i is the exact same motor without any changes to it, but that it's just a marketing ploy to make the 640i/740i owners feel better about their cars' motors.