BMW S14

The BMW S14 is a straight-4 DOHC piston engine which was used in the E30 M3. It is based on the M10 block and the M88 head with two cylinders removed.^[1] The successor to the S14 is the S50 six cylinder engine (since it was used in the following M3).

Two separate throttle bodies are used, each incorporating two throttle butterfly plates.^[2]

Models

S14B20

This version was only sold in Portugal and Italy.^[2] It has a 1990 cc capacity (achieved by shortening the stroke to 72.6 mm)^[1] and produces 141 kW.^[3]

Applications:

• 1987-1990 E30 320iS (Italy and Portugal only)

S14B23

The E30 M3 was initially released with the 147 kW S14B23.^[4] Versions equipped with a catalytic convertor produced 143 kW (194 PS; 192 hp) and 230 Nm.^[4]

Applications:

• 1986-1990 E30 M3

S14B23 EVO2

This update of the S14B23 produced 162 kW (220 PS; 217 hp), or 158 kW (215 PS; 212 hp) if equipped with a catalytic convertor.^[4] Changes include a revised intake camshaft profile and modified exhaust camshaft timing, increased compression, and a more efficient cylinder head intake port design.^{[citation needed]} Larger diameter exhaust header tubes are used.^{[citation needed]}

Applications:

• 1988-1990 E30 M3

S14B25 EVO3

In 1989, the displacement was enlarged to 2467 cc and this engine produced 175 kW.^[4] Higher lift intake and exhaust camshafts were used.^{[citation needed]} Applications:

• 1989-1990 E30 M3

References

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