BMW N55, Manual, Page: 12 / 100

Breakdown of N55 Engine Designation
Engine Identification
The engines are marked on the crankcase with an engine identification code for unique
identification. This engine identifier is also required for approval by the authorities. The
N55 engine further develops this identification system and the code has been reduced
from previously eight to seven characters. The engine serial number can be found under
the engine identifier on the engine. Together with the engine identifier, this consecutive
number enables unique identification of each individual engine.
Index Explanation
N
BMW Group Development
5
Straight 6 engine
5
Engine with direct injection, Valvetronic and exhaust turbocharger
B
Gasoline engine, longitudinal
30
3.0-liter capacity
M
Medium performance class
0
New development
Item Meaning Index / explanation
1
Engine developer
M, N = BMW Group
P = BMW Motorsport
S = BMW M GmbH
W = Non-BMW engines
2
Engine type
1 = R4 (e.g. N12)
4 = R4 (e.g. N43)
5 = R6 (e.g. N55)
6 = V8 (e.g. N63)
7 = V12 (e.g. N73)
8 = V10 (e.g. S85)
3
Change to the basic engine concept
0 = basic engine
1 – 9 = changes, e.g. combustion process
4
Working method or fuel type and
possibly installation position
B = Gasoline, longitudinal installation
D = diesel, longitudinal installation
H = hydrogen
5
Displacement in liters 1 = 1 liter (whole number of liters)
6
Displacement in 1/10 liter 8 = 0.8 liter (tenth of liter)
7
Type test concerns (changes that
require a new type test)
A = Standard
B – Z = Depending on requirement, e.g. RON 87
12
N55 Engine