BMW S14

BMW S14
BMW S14 Engine BMW S14 in an E30 M3
Overview
Manufacturer	BMW
Production	1986-1990
Combustion chamber
Configuration	DOHC straight-4
Chronology
Predecessor	none
Successor	BMW S50

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

Engine	Displacement	Power	Torque	Redline	Year
S14B20	1990 cc	141 kW (192 PS; 189 hp) @ 6900	210 N·m (155 lb·ft) @ 4900	7300	1987-1990
S14B23	2303 cc	147 kW (200 PS; 197 hp) @ 6750	240 N·m (177 lb·ft) @ 4750		1986-1990
S14B23 EVO2	2302 cc	162 kW (220 PS; 217 hp) @ 6750	245 N·m (181 lb·ft) @ 4750		1988-1990
S14B25 EVO3	2467 cc	175 kW (238 PS; 235 hp) @ 7000	240 N·m (177 lb·ft) @ 4750		1989-1990

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:

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

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:

• 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 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.

Applications:

• 1988-1990 E30 M3

S14B25 EVO3

In 1989, the displacement was enlarged to 2467 cc and this engine produced 175 kW (238 PS; 235 BHP). Higher lift intake and exhaust camshafts were used. Applications:

• 1989-1990 E30 M3