The BMW M54 is a naturally aspirated straight-6 petrol engine produced from 2000 to 2006. It was released in the E53 X5 and is the replacement for the M52 engine. The S54 is the equivalent high performance engine, used in the E46 M3, the Z3 M Coupé/Roadster and the E85/E86 Z4 M. The

BMW M56 The BMW M56 is a 2.5 liter 184 PS (135 kW; 181 bhp) straight-six engine. It is a re-engineered version of the BMW M54B25 engine, manufactured in order to meet SULEV regulations in 4 US states. Background The updated 2.5 liter engine ...

SULEV engine (sold in several states of the United States) is based on the M54. The M54 was phased out following the introduction of the

BMW N52 The BMW N52 is a naturally aspirated straight-six petrol engine which was produced from 2004 to 2015. The N52 replaced the BMW M54 and debuted on the E90 3 Series and E63 6 Series. The N52 was the first water-cooled engine to use magnesium/alu ...

engine in 2004. From 2001 to 2003, the M54 was included on the

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 ev ...

list.

Design

Compared with the final versions of its M52 predecessor (called the 'M52TU'), the M54 has a non-return fuel system, a fully electronic throttle (without mechanical backup), Siemens MS 43

engine management An engine or motor is a machine designed to convert one or more forms of energy into mechanical energy. Available energy sources include potential energy (e.g. energy of the Earth's gravitational field as exploited in hydroelectric power gen ...

, a revised

intake manifold In automotive engineering, an inlet manifold or intake manifold (in American English) is the part of an engine that supplies the fuel/air mixture to the cylinders. The word ''manifold'' comes from the Old English word ''manigfeald'' (from the ...

. The

displacement Displacement may refer to: Physical sciences Mathematics and Physics * Displacement (geometry), is the difference between the final and initial position of a point trajectory (for instance, the center of mass of a moving object). The actual path ...

of the largest variant increased from 2.8 L to , due to an increase in stroke to . As per the M52TU, the M54 uses an aluminium block and aluminium cylinder head with cast iron

cylinder liner In a reciprocating engine, the cylinder is the space in which a piston travels. The inner surface of the cylinder is formed from either a thin metallic liner (also called "sleeve") or a surface coating applied to the engine block. A piston is se ...

Variable valve timing In internal combustion engines, variable valve timing (VVT) is the process of altering the timing of a valve lift event, and is often used to improve performance, fuel economy or emissions. It is increasingly being used in combination with varia ...

is fitted to both camshafts (called " double-VANOS"), a dual length intake manifold (called "DISA") is used and the thermostat is electronically controlled. The redline remains at 6,500 rpm. There was no "technical update" (TU) version of the M54 produced, therefore the engine specifications remained the same throughout its seven-year production run.

Versions

M54B22

The M54B22 produces at 6,100 rpm and at 3,500 rpm. Bore is ,

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

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 10.8:1. ;Applications * 2000–2006 E46 320i, 320Ci * 2000–2003 E39 520i * 2000–2002 E36/7 Z3 2.2i * 2003–2005

E85 E85 is an abbreviation typically referring to an ethanol fuel blend of 85% ethanol fuel and 15% gasoline or other hydrocarbon by volume. In the United States, the exact ratio of fuel ethanol to hydrocarbon may vary according to ASTM 5798 that ...

Z4 2.2i * 2003–2005 E60/E61 520i

M54B25

The M54B25 produces at 6,000 rpm and at 3,500 rpm. Bore is , stroke is and the compression ratio is 10.5:1. ;Applications * 2000–2002 E36/7 Z3 2.5i * 2000–2006 E46 325i, 325xi, 325Ci * 2000–2004 E46/5 325ti * 2000–2004 E39 525i * 2003–2005 E60/E61 525i, 525xi * 2003–2006 E83 X3 2.5i * 2002–2005

Z4 2.5i

M54B30

The M54B30 is the largest M54 variant and produces at 5,900 rpm and at 3,500 rpm. Bore is , stroke is and the compression ratio is 10.2:1. In the United States and Canada, a "ZHP" version of the M54B30 used different camshafts and reprogrammed engine management to develop at 5,900 rpm and at 3,500 rpm and have a slightly higher redline of 6,800 rpm (although the Canadian cars still show the limiter at 6,500 rpm on the tachometer). The M54B30 was on the

list through 2001–2003. ;Applications * 2000–2006 E46 330i, 330xi, 330Ci * 2000–2004 E39 530i * 2000–2002 E36/7 Z3 3.0i * 2003–2005 E60 530i * 2002–2005

Z4 3.0i * 2003–2006 E83 X3 3.0i * 2000–2006 E53 X5 3.0i * 2002–2005 E65/E66 730i, 730Li * 2000–2002 Wiesmann MF 30

S54

The S54 was marketed as the high performance equivalent to the M54, however it is actually more an evolution of the

BMW S50 The BMW M50 is a straight-6 DOHC petrol engine which was produced from 1990 to 1996. It was released in the E34 520i and 525i, to replace the M20 engine. In September 1992, the M50 was upgraded to the M50TU ("technical update"), which was BMW' ...

and shares few parts with the M54. As per the S50, the engine block is made of cast iron (unlike the aluminium engine block used by the M54). Redline is 8,000 rpm. Compared with the S50, the S54 features: * Bore increased to , resulting in a

of * Revised

camshaft A camshaft is a shaft that contains a row of pointed cams, in order to convert rotational motion to reciprocating motion. Camshafts are used in piston engines (to operate the intake and exhaust valves), mechanically controlled ignition systems ...

s * Finger follower valve actuation instead of bucket-style tappets. *

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 ...

increased from 11.3:1 to 11.5:1 *

Siemens Siemens AG ( ) is a German multinational conglomerate corporation and the largest industrial manufacturing company in Europe headquartered in Munich with branch offices abroad. The principal divisions of the corporation are ''Industry'', '' ...

MSS 54 Engine control unit *

Electronic throttle control Electronic throttle control (ETC) is an automobile technology which electronically "connects" the accelerator pedal to the throttle, replacing a mechanical linkage. A typical ETC system consists of three major components: (i) an accelerator ped ...

Scavenging Scavengers are animals that consume dead organisms that have died from causes other than predation or have been killed by other predators. While scavenging generally refers to carnivores feeding on carrion, it is also a herbivorous feeding ...

oil pump (to avoid oil starvation during cornering; this was also present on the S50B30 of the E36 M3 GT and the S50B32, but not the regular S50B30) There is no direct successor to the S54, since the following generation of M3 is powered by the BMW S65 V8 engine. However, in 2014, the S65 V8 engine was replaced with an inline-6 engine called the

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 ...

. This is considered the spiritual successor of the S54, being a 6-cylinder engine. This engine was first used in the newly introduced BMW M3 F80 and BMW M4 F82

S54B32

Variations in power and torque outputs are often due to country-specific emissions regulations, or space constraints of a chassis affecting the layout of the intake/exhaust system. ;Applications * 2000–2006 E46 M3 — produces at 7,900 rpm and at 4,900 rpm. Models for the United States and Canada produce and . * 2000–2002 E36/7 Z3 M Roadster, E36/8 M Coupé — produces and . Models for the United States and Canada produce and . * 2002–2011 Wiesmann MF 3 Roadster — produces and . * 2006–2008 E85 Z4 M Roadster, E86 Z4 M Coupé — produces and - Engine code 326S4. Models for the United States and Canada produce and .

S54B32HP

An upgraded version of the S54 engine was used in the E46 M3 CSL. This engine is designated S54B32HP and the changes include a revised intake made from

carbon fiber Carbon fiber-reinforced polymers (American English), carbon-fibre-reinforced polymers (Commonwealth English), carbon-fiber-reinforced plastics, carbon-fiber reinforced-thermoplastic (CFRP, CRP, CFRTP), also known as carbon fiber, carbon compo ...

, revised camshafts, a MAP sensor (instead of the MAF sensor used in the regular S54), a lightweight exhaust manifold with a straighter air path (which later became standard on the regular S54) and a straightened intake manifold. ;Applications * 2003 E46 M3 CSL , * 2009 Wiesmann MF 3 Roadster "20th Anniversary Edition" — produces ,

References

{{BMW automotive petrol engines: 1980s to 2000s M54 Straight-six engines Gasoline engines by model