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. 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.

Models

S14B20

This version was only sold in Portugal and Italy. It has a 1990 cc capacity (achieved by shortening the stroke to 72.6 mm) and produces 141 kW (192 PS) .

Applications:

S14B23

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

Applications:

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 converter. Changes include a revised intake camshaft profile and modified exhaust camshaft timing, increased compression, and a more efficient cylinder head intake port design. Larger diameter exhaust header tubes are used.