View Single Post
      12-12-2009, 07:13 PM   #24
teagueAMX
Colonel
teagueAMX's Avatar
United_States
60
Rep
2,087
Posts

Drives: Some are road worthy
Join Date: Apr 2009
Location: So Cal, USA

iTrader: (0)

The top of the n54 and n55 engines look really different, so in addition to what amdmaxx said "twin turbocharges" but the engine in the bay of the 35is is clearly a n54.

Top photo: n54 dual turbocharged engine (current Z4 35i engine).

Bottom photo: n55 "twin-scroll" single turbocharged engine

You'll notice the engine cover look completely different. On the twin turbo the cover goes all the way front to back with the oil filler cap in the middle. The BMW roundel in the front.

On the single turbo engine, its cover is shortened because the turbocharger induction pipe crosses over the engine. Also, the oil filler cap and BMW roundel are side-by-side at the front of the engine.

The air filter housings look different as well.
Attached Images
  
Appreciate 0