The BMW N55 is a turbocharged straight-six petrol engine that began production in 2009. The N55 replaced the
BMW N54
The BMW N54 is a twin-turbocharged straight-six petrol engine that was produced from 2006 to 2016. It is BMW's first mass-produced turbocharged petrol engine and BMW's first turbocharged petrol engine since the limited-production BMW M106 was disc ...
engine and was introduced in the
F07 5 Series Gran Turismo.
The N55 was
BMW's first straight-six engine to use a
twin-scroll turbocharger
In an internal combustion engine, a turbocharger (often called a turbo) is a forced induction device that is powered by the flow of exhaust gases. It uses this energy to compress the intake gas, forcing more air into the engine in order to pro ...
. It also won three straight
Ward's 10 Best Engines 10 of the World's best engines is an annual list of the ten ''"''best''"'' automobile engines available in the U.S. market, that are selected by ''Ward's AutoWorld'' magazine. The list was started in 1994 for Model Year 1995, and has been drawn eve ...
awards in 2011–2013.
Following the introduction of the
BMW B58
The BMW B58 is a turbocharged straight-six engine, which began production in 2015. The B58 replaced the N55 and was launched in the F30 340i.
The B58 is part of BMW's new modular engine family, each engine using a displacement of per cylind ...
engine in 2015, the N55 began to be phased out.
BMW S55
The BMW N55 is a turbocharged straight-six petrol engine that began production in 2009. The N55 replaced the BMW N54 engine and was introduced in the F07 5 Series Gran Turismo.
The N55 was BMW's first straight-six engine to use a twin-scroll ...
engine is a high performance version of the N55 made by
BMW M GmbH
BMW M GmbH, formerly known as BMW Motorsport GmbH, is a subsidiary of BMW AG that manufactures high-performance cars.
BMW M ("M" for "motorsport") was initially created to facilitate BMW's racing program, which was very successful in the 1960 ...
, which is used by the
F80 M3,
F82 M4 and
F87 M2 Competition/CS.
Design
The main differences between the N55 and its N54 predecessor are the use of a single turbocharger, the addition of Valvetronic and the type of fuel injectors. Whilst the N54 used a twin-turbo arrangement, the newer N55 uses only a single twin scroll turbocharger.
Valvetronic
The Valvetronic system is a BMW variable valve lift system which, in combination with VANOS, allows infinite adjustment of the intake valve timing and duration. The system claims to improve fuel economy and emissions, and negates the need for a ...
(variable valve lift)
is claimed to improve throttle response, low-rev torque, exhaust emissions and to reduce fuel consumption by 15%.
The
direct injection system uses solenoid-type injectors, instead of the piezo-type fuel injectors used by its N54 predecessor. The piezo injectors were more expensive and BMW decided they were not worthwhile outside of Europe, because the potential benefits of lean-burn operation could not be fully realised.
The exhaust manifold design, called ''Cylinder-bank Comprehensive Manifold (CCM)'' by BMW, aims to reduce the pressure fluctuations to reduce throttle lag and exhaust back-pressure. The twin-scroll turbocharger uses 2 sets of exhaust duct to turn 1 turbine wheel, with cylinders 1–3 and 4–6. The
engine management system
An engine control unit (ECU), also commonly called an engine control module (ECM), is a type of electronic control unit that controls a series of actuators on an internal combustion engine to ensure optimal engine performance. It does this by re ...
is Bosch MEVD 17.2, and compatible fuels are ROZ (RON) 91–98 octane (minimum RON 95 is recommended),
As per the N54, the
compression ratio
The compression ratio is the ratio between the volume of the cylinder and combustion chamber in an internal combustion engine at their maximum and minimum values.
A fundamental specification for such engines, it is measured two ways: the stati ...
is 10.2:1, the
bore is , the
stroke
A stroke is a medical condition in which poor blood flow to the brain causes cell death. There are two main types of stroke: ischemic, due to lack of blood flow, and hemorrhagic, due to bleeding. Both cause parts of the brain to stop functionin ...
is and the displacement is .
Versions
N55B30M0
Applications:
* 2009–2017
F10/F11/F07 535i
* 2010–2013
E90/E91/E92/E93 335i
* 2010–2013
E82/E88 135i
* 2010–2017
F25 X3 xDrive35i
* 2011–2013
E70 X5 xDrive 35i
* 2011–2015
F30/F31 335i
* 2011–2014
E71 X6 xDrive 35i
* 2012–2015
E84 X1 xDrive35i
* 2013–2016
F32/F33/F36 435i
* 2014–2018
F15 X5 xDrive 35i
* 2014–2019
F16 X6 xDrive35i
* 2014–2016
F26 X4 xDrive 35i
N55B30
Applications:
* 2011–2018
F06/F12/F13 640i
* 2012–2013
E82/E88 135is
* 2012–2015
F20/F21 M135i
* 2012–2015
F01/F02 740i/Li
N55B30O0
Applications:
* 2013–2016
F22/F23 M235i
* 2015–2016
F20/F21 M135i LCI
N55HP
Applications:
* 2013–2015
F30 ActiveHybrid 3
* 2011–2016
F10 ActiveHybrid 5
N55B30T0
Applications:
* 2016–2018
F87 M2 —
* 2015–2018
F26 X4 M40i —
Alpina
Biturbo engine by
Alpina
Alpina Burkard Bovensiepen GmbH & Co. KG is an automobile manufacturing company based in Buchloe, in the Ostallgäu district of Bavaria, Germany that develops and sells high-performance versions of BMW cars.
Alpina works closely with BMW and ...
based on the N55B30M0. The crankcase is of a different design and specially cast by BMW for Alpina.
301 kW version
The N55R20A is Alpina's initial version of the N55, producing . The twin turbocharger system of the N54B30 is used, replacing the twin-scroll charging system originally applied.
Applications:
* 2013–2017
Alpina F30 B3 Bi-Turbo
* 2013–2017
Alpina F33/F34 B4 Bi-Turbo
324 kW version
Applications:
* 2017–present Alpina F30/F31 B3 S Bi-Turbo
* 2017–present Alpina F32/F33 B4 S Bi-Turbo
332 kW version
Application:
* 2018–present
Alpina F32/F33 B4 S Bi-Turbo Edition 99
S55 engine
The S55 engine is the high performance version engine developed from the N55 engine by BMW M. It was introduced in the
F80 M3,
F82 M4 and later to the
F87 M2 Competition/CS, replacing the
BMW S65 naturally aspirated V8 engine used in the previous generation M3.
Differences compared with the N55 include a closed-deck engine block, lightweight crankshaft, different crankshaft bearings, strengthened pistons/rods, different springs/valve material, twin turbos, twin fuel pumps, active exhaust, revised cooling system and intercoolers.
– version
Applications:
* 2020–present
F87 M2 CS Racing
version
Applications:
* 2019–2021
F87 M2 Competition
version
Applications:
* 2014–2018
F80 M3
* 2014–2020
F82/F83 M4
version
Applications:
* 2016–2018
F80 M3 with Competition package
* 2016–2020
F82/F83 M4 with Competition package
*2020–2021
F87 M2 CS
version
Applications:
* 2018
F80 M3 CS
* 2017–2020
F82 M4 CS
version
This version produces and , due to the use of a
water injection system. Three water injectors are used to lower the temperature of the air in the intake manifold, allowing the boost pressure to be increased from to .
Applications:
* 2015–2016
F82 M4 GTS
* 2017 F82 M4 DTM Champion Edition
See also
*
List of BMW engines
BMW has been producing engines for automobiles, motorcycles and aircraft since 1917, when the company began production of an inline-six aircraft engine. They have been producing automobile engines since 1933.
Motorcycle engines
Automotive ...
References
{{BMW automotive petrol engines: 2000s to 2010s
N55
Products introduced in 2009
Straight-six engines
Gasoline engines by model