BMW M10

The BMW M10 is a SOHC inline-4 petrol engine which was produced by BMW from 1962-1988. It was the company's first four-cylinder engine since the BMW 309 ended production in 1936 and was introduced in the New Class sedans.

The M10 was used in many BMW models, with over 3.5 million being produced during its 26 year production run.

The turbocharged BMW M12 engine— used in the Formula One racing— was based on the M10 engine block and produced up to in qualifying trim.

Following the introduction of the BMW M40 engine in 1987, the M10 began to be phased out.

Development

Baron Alex von Falkenhausen — an engineer and racing driver — designed the M10 in the late 1950s. He was asked by BMW to design an engine with a displacement of , but felt that this would be insufficient for the company's future needs. He convinced management that the minimum capacity should be , and offered an engine that could be expanded to a maximum of .

Design

The M10 has a cast iron block and an aluminum alloy head with hemispherical combustion chambers and two valves per cylinder. It features a forged crankshaft, counterbalance weights, five main bearings and a chain-driven camshaft.

The initial version of the M10 had a bore of and a stroke of , resulting in a displacement of . The peak power rating was Template:Cvt.

Naming conventions

The engine was initially known as the "M115" (the last two digits representing the 1.5–litre capacity). Over the years, variants of the engine were given various codes (most of them starting with "M1" and the remaining digits relating to the capacity). In 1975, the engine became known as the "M10", then in 1980 it was given the standardised BMW engine code of M10B18 (where "M10" represents the series, B represents petrol (Benzin in German) and the "18" represented its then 1.8–litre capacity).

The M115 and all related engines have become retroactively known as the "M10" family.

Versions

Version	Displacement	Power	Torque	Year
M115		Template:Cvt at 5800 rpm	at 3700 rpm	1974–1977
		Template:Cvt at 5700 rpm	at 3000 rpm	1962-1964
M116		Template:Cvt at 5800 rpm	at 3500 rpm	1964–1975
		Template:Cvt at 6000 rpm	at 4500 rpm	1967–1968
M41		Template:Cvt at 6000 rpm	at 4000 rpm	1975-1980
M98		Template:Cvt at 5800 rpm	at 3200 rpm	1981-1983
M10B18		Template:Cvt at 5800 rpm	at 3500 rpm	1980-1983
		Template:Cvt at 5800 rpm Template:Cvt	at 4500 rpm	1980–1988 S/CH
M118		Template:Cvt at 5,250 rpm	at 3000 rpm	1963–1974
		Template:Cvt at 5800 rpm	at 4000 rpm	1964–1976
		Template:Cvt at 6100 rpm	at 5100 rpm	1964-1965
M05		Template:Cvt at 5500 rpm	at 3000 rpm	1968–1976
		Template:Cvt at 5600 rpm	at 3500 rpm	1965–1971
M17		Template:Cvt at 5800 rpm	at 3700 rpm	1972-1977
M15		Template:Cvt at 5800 rpm	at 4500 rpm	1970–1974
M43		Template:Cvt at 5800 rpm	at 3700 rpm	1975-1983
M64		Template:Cvt at 5700 rpm	at 4350 rpm	1975-1979
M10B20		Template:Cvt at 5700 rpm	at 4350 rpm	1977-1979
M31	turbo	Template:Cvt at 5800 rpm	at 4000 rpm	1973-1975

1499 cc engines

The M115 version has a displacement of and produces . It has a bore of and a stroke of . Lower power models have a compression ratio of 8.0:1, while higher power models have a compressions ratio of 8.8:1. Fuel is supplied via a Solex 38 PDSI carburettor.

Applications:

• 1962-1964 BMW 1500
• 1975-1977 BMW 1502

1573 cc engines

The M116 version has a displacement of and produces . It has a bore of and a stroke of . The standard specification has a compression ratio of 8.6:1 and uses a Solex 38 PDSI carburettor. The 1600 ti version has a compression ratio of 9.5:1 and uses twin Solex 40 PHH carburettors.

Applications:

• 1964-1966 BMW 1600—
• 1966-1975 BMW 1600-2/1602—
• 1967-1968 BMW 1600 ti—

The M41 version produces Template:Cvt, has an 8.3:1 compression ratio and fuel is supplied by a Solex 32 DIDTA carburettor.

Applications:

• 1975-1980 E21 316

The M98 version produces , has a compression ratio of 9.5:1 and uses a Pierburg 1B2 carburettor.

Applications:

• 1981-1983 E21 315

1766 cc engines

The M10B18 version has a displacement of Template:Cvt and produces Template:Cvt, depending on specification. The bore is and the stroke is .

Applications:

• 1969-1972 1800— , 8.6:1 compression, Solex 36-40 PDSI carburettor
• 1971-1975 1802— , 8.6:1 compression, Solex 38 PDSI carburettor
• 1980-1983 E21 320i/320is— U.S. only, , 8.8:1 compression, Bosch K-Jetronic mechanical fuel injection
• 1980-1983 E12 518— South Africa only, , 10.0:1 compression, Bosch K-Jetronic mechanical fuel injection
• 1982-1987 E30 316 — , 9.5:1 compression, Pierburg 2BE carburettor, Ecotronic.
• 1982-1988 E30 318i— , 10.0:1 compression, Bosch L-Jetronic electronic fuel injection
• 1981-1988 E28 518i— , 9.5:1 compression, Bosch LE-Jetronic mechanical fuel injection.

1773 cc engines

The M118 version has a displacement of Template:Cvt and produces Template:Cvt, depending on specification. The bore is and the stroke is .

Applications:

• 1963-1968 1800— Template:Cvt, 8.6:1 compression, Solex 36-40 PDSI carburettor
• 1963-1966 1800ti— Template:Cvt, 9.5:1 compression, twin Solex 40 PHH carburettors
• 1964-1965 1800tiSA— Template:Cvt, 10.5:1 compression, twin Weber DCOE-45 carburettors
• 1974-1981 E12 518— Template:Cvt, 8.6:1 compression, Solex 38 PDSI carburettor

1990 cc engines

The M05 version has a displacement of Template:Cvt and produces Template:Cvt, depending on specification. It has a bore of Template:Cvt and a stroke of Template:Cvt.

Applications:

• 1965-1970 BMW 2000CS— Template:Cvt, 9.3:1 compression, 2x Solex 40 PHH carburettors
• 1966-1970 BMW 2000C— Template:Cvt, 8.5:1 compression, Solex 40 PDSI carburettor
• 1966-1972 BMW 2000— Template:Cvt, 8.5:1 compression, Solex 40 PDSI carburettor
• 1966-1971 BMW 2000ti— Template:Cvt, 9.3:1 compression, 2x Solex 40 PHH carburettors
• 1968-1976 BMW 2002— Template:Cvt, 8.5:1 compression, Solex 40 PDSI carburettor

The M15 version used the Kugelfischer mechanical fuel injection and produced Template:Cvt. It was also known as the tii engine.

Applications:

• 1970-1973 2000tii
• 1972-1974 2002tii
• 1972-1974 E12 520i

The M17 version produces Template:Cvt. It has compression ratio of 9.0:1 and uses either a Stromberg 175 CDET or a Solex 4A1 carburettor.

Applications:

• 1972-1977 E12 520

The M43/1 version has a compression ratio of 8.1:1 and produces .

Applications:

• 1975-1979 E21 320— Solex 32-32 DIDTA carburettor
• 1975-1979 E21 320i— USA only, Bosch K-Jetronic mechanical fuel injection

The M64 version produces . It has a compression ratio of 9.3:1 and uses Bosch K-Jetronic mechanical fuel injection.

Applications:

• 1975-1978 E21 320i
• 1975-1979 E12 520i

The M31 version uses a KKK BLD turbocharger operating @ 7psi and produces . It has a compression ratio of 6.9:1 and uses Schafer PL 04 mechanical fuel injection.

Applications:

• 1973-1975 2002 turbo

Related engines

• The highly successful M12 turbocharged motorsport engine was based on the M10 engine block.

• The S14 engine used in the E30 M3 was based on the M10 block.

See also

• List of BMW engines