BMW S14

The BMW S14 was a double overhead camshaft four-cylinder petrol engine used in the E30 M3, the E30 320iS and the E36 318i Super Touring. It was based on the block of the M10 and what is essentially a shortened cylinder head from the S38, and it used two separate throttle bodies, each with two butterfly plates. The E30 M3 first received the 2.3 litre S14B23 at 147 kW, a catalytic converter version gave 143 kW, and later limited editions and the standard motor reached 158 kW. The EVO2 update gave 162 kW, and a 2.5 litre S14B25 EVO3 gave 175 kW in 1989. A 1,990 cc S14B20 was sold only in Portugal and Italy to benefit from tax on engines under two litres. The S42 racing engine succeeded it, and the next M3 used the S50 six.