The BMW S14 is a DOHC four-cylinder petrol engine which was used in the

E30 M3 The BMW M3 is a high-performance version of the BMW 3 Series, developed by BMW's in-house motorsport division, BMW M GmbH. M3 models have been produced for every generation of 3 Series since the E30 M3 was introduced in 1986. The initial mode ...

, E30 320iS, and E36 320i Super Touring. It is based on the

BMW M10 The BMW M10 is an SOHC four-cylinder petrol engine which was produced from 1962-1988. It was BMW's first four-cylinder engine since the BMW 309 ended production in 1936 and was introduced in the New Class sedans. Over 3.5 million M10 engines w ...

block and the cylinder head from the six-cylinder

BMW S38 The BMW S38 is a straight-6 DOHC petrol engine which replaced the M88 and was produced from 1984-1995. The S38 was originally produced for North America as an equivalent to the M88 with slightly lower power output. In 1989, power output of the S3 ...

with two cylinders removed. The direct successor to the S14 was the S42 based on the M42 engine. The S42 was a racing engine installed in the E36 320i for the German Super Tourenwagen Cup. There is no direct successor to the S14 for production BMWs, since the following generation of M3 is powered by 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' ...

six-cylinder engine. Two separate throttle bodies are used, each incorporating two throttle butterfly plates.

Versions

S14B20

This version was only sold in Portugal and Italy. It has a

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 ...

reduced to by shortening 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 ...

to . Applications: * 1987-1990 E30 320iS (Italy and Portugal only)

S14B23

The

was initially released with the S14B23 engine. Versions equipped with a

catalytic converter A catalytic converter is an exhaust emission control device that converts toxic gases and pollutants in exhaust gas from an internal combustion engine into less-toxic pollutants by catalyzing a redox reaction. Catalytic converters are usually ...

produced and 230 Nm. In April 1989, the Ravaglia and Cecotto limited edition M3s were released with a S14B23 that would in September, 1989 become the standard motor for the E30 M3. Applications: * 1986-1991

S14B23 EVO2

This update of the S14B23 produced , or if equipped with a catalytic converter. Applications: * 1988-1990

S14B25 EVO3

In 1989, the displacement was enlarged to and this engine produced . Applications: * 1989-1990

References