| BMW M70 engine | |
|---|---|
 | |
| Overview | |
| Production | 1987–1994 |
| Layout | |
| Configuration | 60°V12 |
| Displacement | 5.0 L (4,988 cc) |
| Cylinder bore | 84 mm (3.31 in) |
| Piston stroke | 75 mm (2.95 in) |
| Cylinder block material | Aluminium |
| Cylinder head material | Aluminium |
| Valvetrain | SOHC |
| Combustion | |
| Fuel type | Petrol |
| Output | |
| Power output | 220 kW (295 hp) |
| Torque output | 450 N⋅m (332 lb⋅ft) |
| Chronology | |
| Predecessor | None |
| Successor | BMW M73 |
TheBMWM70 is anaturally-aspirated,SOHC,V12petrol engine, which was BMW's first production V12[1] and was produced from 1987 to 1996. It was also the first German 12-cylinder post-war automobile engine, predatingMercedes-Benz's M120 by four years andVW'sW12 by fourteen.
The BMWS70/2 engine, largely unrelated to the M70 and S70B56 engines, is a naturally-aspirated,DOHC, V12 petrol engine, which powered the 1993 to 1998McLaren F1.
The M70's design is similar to that of two 2.5 LM20 straight-six engines joined at a 60-degree angle,[2] due to the following features:single overhead camshaft valvetrain, bore spacing of 91 mm (3.6 in),bore of 84 mm (3.31 in),stroke of 75 mm (2.95 in), and acompression ratio of 8.8:1.[3]
The M70 has the following differences with the M20 engine:
The M70 has twoMotronic 1.3[7]ECUs (one for each cylinder bank). To provide redundancy, the M70 also has two fuel pumps, fuel rails, distributors, mass air flow sensors, crankshaft position sensors, coolant temperature sensors and throttle bodies.[8]
Some M70 engines (such as fitted to theE32 750iL Highline) are fitted with twoalternators. The second alternator is smaller and is used to charge an auxiliary battery and power equipment in the rear passenger compartment, such as a telephone, fax machine, wine cooler, independent climate control and power sun shields.[9]
| Version | Displacement | Power | Torque | Redline | Years |
|---|---|---|---|---|---|
| M70B50 | 4,988 cc (304.4 cu in) | 220 kW (295 hp)[10] at 5,200 rpm | 450 N⋅m (332 lb⋅ft) at 4,100 rpm | 6,000 | 1987–1994 |
| S70B56 | 5,576 cc (340.3 cu in) | 280 kW (375 hp) at 5,300 rpm | 550 N⋅m (406 lb⋅ft) at 4,000 rpm | 6,400 | 1992–1996 |
| S70/2 | 6,064 cc (370.0 cu in) | 461 kW (618 hp) at 7,400 rpm | 617 or 651 N⋅m (455 or 480 lb⋅ft) at 6,700 rpm | 7,500 | 1993–1998 |
| S70/3 | 5,990 cc (365.5 cu in) | 467 kW (626 hp) at 6,500 rpm[a] | 670 N⋅m (494 lb⋅ft) at 4,500 rpm | 8,000 | 1998–2000 |
Applications:
| BMW S70 engine | |
|---|---|
 Engine bay of aMcLaren F1 | |
| Overview | |
| Production | 1992–2000 |
| Layout | |
| Configuration | 60°V12 |
| Displacement | 5.6 L (5,576 cc) 6.1 L (6,064 cc) 6.0 L (5,990 cc) |
| Cylinder bore | 86 mm (3.39 in) |
| Piston stroke | 80 mm (3.15 in) 87 mm (3.43 in) 85.9 mm (3.38 in) |
| Cylinder block material | Aluminium |
| Cylinder head material | Aluminium |
| Valvetrain | DOHC, withVVT |
| Compression ratio | 11:1 |
| Combustion | |
| Fuel type | Petrol |
| Cooling system | Water-cooled |
| Output | |
| Power output | 280–671 kW (375–900 hp)*(*900 PS produced only McLaren F1 GTR Long Tail specifically in full race trim upon qualification without racing restrictors)[13][14][15][16] |
| Torque output | 550–900 N⋅m (406–664 lb⋅ft) |
| Dimensions | |
| Dry weight | 265 kg (584 lb) |
| Chronology | |
| Predecessor | None |
| Successor | None |
The first engine to use the S70 name is a 5,576 cc (340.3 cu in) variant of the M70 engine fitted only to the E31 850CSi.[17] With 1,510 units produced, this is the lowest production number BMW-engine, for a BMW-car to date.[18]
Three prototypedual overhead camshaft S70 engines were constructed, prior to the decision to not produce an E31 M8 model.[19]
Applications:
The S70/2, while sharing the same 12 cylinder layout, bore spacing and design principle as the S70B56, is essentially a new design with the heads based on the European marketS50B30,[20] and thus featuring 4 valves per cylinder andvariable valve timing (calledVANOS by BMW) and individual throttle bodies. Adry sump oiling system is used.[21] The weight of the S70/2, plus ancillaries and full exhaust, is 265 kg (584 lb).[22]
Applications:
The S70/3 is a racing engine based on the S70/2.
Applications
