|BMW M50 engine|
The BMW M50 is a straight-6 DOHC piston engine was produced from 1990-1996. It was released in the E34 520i and 525i, to replace the M20 engine. It began to be phased out following the introduction of the M52 engine in 1994.
Compared with its M20 predecessor, the M50 features DOHC, 4 valves per cylinder, coil-on-plug ignition, a knock sensor and a lightweight plastic intake manifold. As per the M20, the M50 uses an iron block with an alloy head.
|M50B20||1,991 cc (121 cu in)||110 kW (148 bhp) @ 6000||190 N·m (140 lb·ft) @ 4700||6500||80 mm (3.1 in)||66 mm (2.6 in)||10.5||1990|
|M50B20TU||110 kW (148 bhp) @ 5900||190 N·m (140 lb·ft) @ 4200||6500||80 mm (3.1 in)||66 mm (2.6 in)||11.0||1993|
|M50B24||2,394 cc (146 cu in)||138 kW (185 bhp) @ 5900||235 N·m (173 lb·ft) @ 4700||6550||1991|
|M50B25||2,494 cc (152 cu in)||141 kW (189 bhp) @ 5900||245 N·m (181 lb·ft) @ 4700||6500||84 mm (3.3 in)||75 mm (3.0 in)||10.0||1990|
|M50B25TU||141 kW (189 bhp) @ 5900||245 N·m (181 lb·ft) @ 4200||6500||84 mm (3.3 in)||75 mm (3.0 in)||10.5||1993|
|S50B30||2,990 cc (182 cu in)||210 kW (282 bhp) @ 7000||320 N·m (236 lb·ft) @ 3600||7280||86 mm (3.4 in)||86 mm (3.4 in)||10.8||1992|
|S50B30US||179 kW (240 bhp) @ 6000||305 N·m (225 lb·ft) @ 4250||6500||86 mm (3.4 in)||86 mm (3.4 in)||10.5||1993|
|S50B32||3,201 cc (195 cu in)||236.3 kW (317 bhp) @ 7400||350 N·m (258 lb·ft) @ 3250||7600||86.4 mm (3.4 in)||91 mm (3.6 in)||11.3||1995|
The 2,494 cc (152 cu in) M50B25 was introduced with the 1990 525i and 525ix. It has an 84 mm (3.3 in) bore and 75 mm (3.0 in) stroke and produces 141 kW (189 hp) at 6000 rpm and 245 N·m (181 lb·ft) at 4700 rpm.
The S50 is the high performance version of the M50 which was used in the M3. Like the M50, it has an iron block and aluminum head with four valves per cylinder.
The S50B30 is a 2,990 cc (182 cu in) higher output version of the M50 which powered the E36 M3, except in the USA. Canada had a limited production run of 45 cars with the S50B30 engine.
Engine management is provided by a Bosch Motronic M3.3 ECU with a separate "VNC" Vanos control unit providing fully variable single camshaft adjustment on the intake side. It produces 210 kW (282 hp), has a bore of 86 millimetres (3.4 in) and a stroke of 86 millimetres (3.4 in), and a compression ratio of 10.8:1. The limited edition "M3 GT" model from 1995 had different camshafts and a redesigned sump and oil pump, and produced 216 kW (290 hp).
Upgrades over the M50 include:
- Individual throttle plates for each cylinder
- Continuously variable "Vanos" valve timing.
- Lightweight pistons
- Graphite-coated connecting rods
- Larger inlet valves
- Redesigned equal length exhaust manifolds
- 1992-1995 E36 M3 (except for USA)
USA versions of the 1994-1995 E36 M3 are powered by a 3.0L tuned version of the M50 which produces 179 kW (240 hp). This engine was based on the M50B25TU and uses the same compression ratio, but uses a different crankshaft, connecting rods, and pistons. At the 1996 facelift, this engine was replaced by the 3.2 L S52.
- 1994-1995 E36 M3 (USA only)
In 1996, the 3,201 cc (195 cu in) S50B32 replaced the S50B30 (except in Canada and USA, where the M52-based S52 engine was used instead). Engine management is provided by a Siemens MSS50 engine control unit featuring integrated Vanos control for both the intake and exhaust camshafts. The MSS50 ECU also encompassed an advanced knock control system which can monitor each of the s50b32 6 cylinders via 3 knock sensors allowing the engine run a more refined calibration on standard high octane pump gas. The oil sump is a smaller capacity unit first seen on the M3GT and features a dual pick-up system to lower the risk of oil being forced away from a single pick-up point under cornering. This engine produces 236 kW (316 hp). The compression ratio is 11.3:1, the bore is 86.4 mm (3.4 in) and the stroke is 91 mm (3.6 in).
- 1996-1999 E36 M3 (except Canada and USA)
- 1996-1999 Z3 M coupe and M roadster (except Canada and USA)
- "BMW M50 M52 M54 Engines". www.unixnerd.demon.co.uk.
- "The BMW Six Cylinder Guide". www.autospeed.com.
- "BMW M50 engine". www.usautoparts.net.
- "Engine specifications- M50". www.bmwheaven.com.
- Hudock, Greg. BMW E - Series Restoration Bible. Brooklands Books. p. 8-6. ISBN 9781855209701.
- "Engine specifications- S50 B30 US". www.bmwheaven.com.
- "1994 BMW E36 3 Series Coupe M3 Automatic (US spec)". www.ultimatespecs.com.
- "E36 M3 coupe model selection- March 1996 in USA spec". www.realoem.com.
- "BMW M Registry - FAQ E36 M3 3.0". www.bmwmregistry.com.
- "1993 BMW M3 E36". www.carfolio.com.
- "1995-1999 BMW M3". www.motortrend.com.
- "BMW E36 3-series Coupé specs". www.specs4bmw.com.
- "BMW M Registry - FAQ E36/8 M coupe". www.bmwmregistry.com.
- "Engine specifications- S50B32 Euro". www.bmwheaven.com.
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|4-cylinder petrol||<< M10||M40||M43||N40 / N42||N43 / N45 / N46 >>|
|6-cylinder petrol||<< M20||M50||M52||M54 / M56||N52||N53 >>|
|S50 / S52||S54|
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|8-cylinder petrol||M60||M62||N62||N63 >>|
|12-cylinder petrol||M70||M73||N73||N74 >>|