Originally Posted by ozinaldo
They did not forget the 335is, 335is is a market specific model limited to only US (and UK maybe?) plus 1M and Z4is versions have the highest output of 250 kw/340ps so they considered those two.
The N54 is a twin power in the sense of a bi-turbo set up with two small turbos. The N55 is a single turbo set up but with twin scroll technology.
gotcha on the 335is part
but for the twin power thing, they call all their new twin scroll single turbos "twinpower turbo" they never said that about the n54