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BMW M10/M12
SuccessorBMW M40
ClassSOHC Straight-4
Engine(s)1.5 L (1499 cc/91 in³)
1.6 L (1573 cc/95 in³)
1.8 L (1766 cc/107 in³)
1.8 L (1773 cc/108 in³)
2.0 L (1990 cc/121 in³)
RelatedBMW S14
ManualsService Manual

The BMW M10/M12 was an I4 piston engine produced from 1961 to 1987. Displacement ranged from 1499 cm3 to 1990 cm3.

The engine was designed by noted engineer and race driver Baron Alex von Falkenhausen. He was asked to design a small-displacement (1.3 L) engine, but felt that this would be insufficient for the company's future needs. Therefore, he designed a block that could be expanded to 2.0 L and delivered it at 1.5 L.

The design was very successful, with over 3.5 million produced, and it served the company for over 20 years.

As BMW M12, the engine is also one of the most successful engines in racing. Starting with the European Touring Car Championship, it was also used in Formula 2 and in the Deutsche Rennsport Meisterschaft, where it was turbocharged by Paul Rosche according to FIA Group 5 rules.

The M12 went on to Formula 1, winning the 1983 championship for Nelson Piquet and Brabham — something which very few 20 year old road car engine designs accomplish. The same applies for the rise in power: twenty-fold from 75 hp to about 1500 hp.

The BMW S14 engine for the first BMW M3 was based upon the M10 block. In the M3, the M10 block design is still winning races today.

The BMW M40 series of engines replaced the M10 in the late 1980s.

Formula One history

Brabham had tested a BMW turbocharged engine in the summer of 1981, and for the 1982 Formula One season the new BT50 was designed around it. Brabham thus became the third team after Renault and Ferrari to employ a turbo engine.

Initially the turbo engine's electronics had reliability and driveability issues. The BMW and Brabham relationship came close to ending, with BMW insisting that Brabham stop using the Cosworth powered BT49Ds, while Ecclestone maintained that the BMW powered cars were not reliable enough. Together with Bosch, the BMW engineers solved the problem. The partnership took its first win at the 1982 Canadian Grand Prix. In 1983 Nelson Piquet became the first driver to win the world championship in a turbo-engined car.

Murray's radical long and low BT55 was fitted with a revised BMW engine tilted over to allow clean airflow to the rear wing. The design was not successful, scoring only two points in the 1986 Formula One season; the engine did not perform well in this orientation and the gearbox from Weissman was unreliable.

From 1986 onwards BMW wound down their Formula One involvement. In 1987 Brabham continued to use the 'tilted' units, as the upright versions had been sold to other teams under the Megatron name — they were used by Arrows and Ligier with moderate success. BMW, whose programme was based around turbocharged versions of their road engines, withdrew from Formula One after the 1987 season. The Megatron badged units were used until the end of 1988.


The 1.5 L (1499 cc/91 in³) M115 produced 75 hp or 80 hp (56 kW or 60 kW) (depending on carburetor) and 118 ft·lbf (160 N·m).



The 1.8 L (1773 cc/108 in³) M118 produced 90 hp to 130 hp (67 kW to 97 kW) and 143 to 150 ft·lbf (194 to 203 N·m).



The 1.6 L (1573 cc/95 in³) M116 produced 75 hp to 105 hp (56 kW to 78 kW). Bore was 84 mm and stroke was 71 mm.



The 2.0 L (1990 cc/121 in³) M05 produced 100 hp to 120 hp (75 to 90 kW) and 157 ft·lbf to 167 ft·lbf (213 to 226 N·m). Bore was 89 mm and stroke was 80 mm.



The 2.0 L (1990 cc/121 in³) M15 produced 130 hp (97 kW) and 177 ft·lbf (240 N·m). It was the famed tii engine.



The 2.0 L (1990 cc/121 in³) M17 produced 115 hp (86 kW) and 162 ft·lbf (220 N·m).



The 2.0 L (1990 cc/121 in³) M31 was turbocharged and produced 170 hp (127 kW) and 240 ft·lbf (325 N·m).



The 1.6 L (1573 cc/95 in³) M41 produced 90 hp (67 kW) and 123 ft·lbf (167 N·m).



The 2.0 L (1990 cc/121 in³) M64 produced 125 hp (93 kW) and 172 ft·lbf (233 N·m).



The 2.0 L (1990 cc/121 in³) M43/1 produced 109 hp (81 kW) and 157 ft·lbf (213 N·m).



The 1.8 L (1766 cc/107 in³) M10 produced 98 hp (73 kW) and 142 ft·lbf (193 N·m).



The 1.6 L (1573 cc/95 in³) M98 produced 75 hp (56 kW) and 110 ft·lbf (149 N·m).



The 1.8 L (1766 cc/107 in³) M10B18 (also known as the M98) produced 90 hp (105hp with L-jetronic injection)(67 kW) and 137 ft·lbf (145 N·m).


Engine Displacement Power Torque Redline Year
M10B18 1.8 L (1766 cc/107 in³) 77 kW (103 hp) @ 5800 145 N·m (106 ft·lbf) @ 4500 1980
M10B18 1.8 L (1766 cc/107 in³) 75 kW (100 hp) @ 5800 140 N·m (103 ft·lbf) @ 4500 1985
M10B18 1.8 L (1766 cc/107 in³) 77 kW (103 hp) @ 5800 145 N·m (106 ft·lbf) @ 4500 1980
M10B18 1.8 L (1766 cc/107 in³) 75 kW (100 hp) @ 5800 140 N·m (103 ft·lbf) @ 4500 1985
M10B18V 1.8 L (1766 cc/107 in³) 66 kW (88 hp) @ 5500 140 N·m (103 ft·lbf) @ 4000 1981
M10B18V 1.8 L (1766 cc/107 in³) 66 kW (88 hp) @ 5500 140 N·m (103 ft·lbf) @ 4000 1981

M10B18 had a 89 mm bore and 71 mm stroke. Also, in E30 as 318i, very unusual for that time, it could stretch the 2nd gear all the way to 100 km/h.