The BMW M50 is an I6 piston motor. It was introduced in 1989 to change M20 one and was replaced by the M52 motor in 1994. Displacement ranges from 2.0 L to 3.0 L. It is a DOHC 24-valve engine. A Technical Update or M50TU version from 1992 introduced VANOS variable valve timing.
The M50 was related to the M20 with the same 91 mm cylinder spacing, bore, and stroke at 2.0 L and 2.5 L.
M50B20
The 2.0 L (1991 cc) M50B20 was introduced with the 1989 520i. It has an 80 mm bore and 66 mm stroke and produces 150 hp (110 kW).
This is a 2.4 L engine based on the 2.5 L M50B25, with a reduced stroke. This engine is only fitted to CKD kits assembled in Thailand. Power output is 188 hp (140 kW) and torque is 177 ft.lbf (240 Nm).
The S50B30US was a 3.0 L version, which powered the US-spec E36 M3. Power was 240 hp (179 kW).
Applications:
* 1995 E36 M3
S50B30
The S50B30 was a special sports-oriented 3.0 L version, which powered the RoW spec E36 M3. Power is 286 hp (210 kW). The S50B30 has a bore of 86mm and a stroke of 85.8mm, with a total displacement of 2990cc.
Applications:
* 1992-1995 E36 M3
S50B32
The S50B32 was an evolution version of the S50B30. Power of the 3.2 L version is 321hp. This engine has a bore of 86.4mm and a stroke of 91.0mm giving a displacement of 3201cc.
Applications:
* 1996-1999 E36 M3 * 1997-2000 M Roadster * 1998-2000 M Coupe
