The BMW S14 is a DOHC four-cylinder petrol engine which was used in the E30 M3. It is based on the BMW M10 block and the cylinder head from the six-cylinder BMW S38 with two cylinders removed.[1] There is no direct successor to the S14, since the following generation of M3 is powered by the BMW S50 six-cylinder engine.

Two separate throttle bodies are used, each incorporating two throttle butterfly plates.

S14B20 1,990 cc (121.4 cu in) 141 kW (189 bhp)
at 6,900 rpm 210 N⋅m (155 lb⋅ft)
at 4,900 rpm 1987-1990
S14B23 2,302 cc (140.5 cu in) 143 kW (192 bhp)
at 6,750 rpm 230 N⋅m (170 lb⋅ft)
at 4,750 rpm 1986–1989
147 kW (197 bhp)
at 6,750 rpm 240 N⋅m (177 lb⋅ft)
at 4,750 rpm 1986–1989
158 kW (212 bhp)
at 6,750 rpm 230 N⋅m (170 lb⋅ft)
at 4,600 rpm 1989–1991
S14B23 EVO2 162 kW (217 bhp)
at 6,750 rpm 245 N⋅m (181 lb⋅ft)
at 4,750 rpm 1988-1990
S14B25 EVO3 2,467 cc (150.5 cu in) 175 kW (235 bhp)
at 7,000 rpm 240 N⋅m (177 lb⋅ft)
at 4,750 rpm 1989-1990