Template:Use dmy dates Template:Infobox automobile engine

The BMW M88 is a straight-6 DOHC petrol engine which was produced from 1978 to 1989. It is based on the DOHC version of the BMW M49 engine, which was used in the BMW 3.0CSi racing cars.<ref name="gtspirit.com">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref name="mydriftfun.com">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

The M88 was produced alongside the BMW M30 engine, as the higher performance engine. In North America up until 1989, the BMW S38 engine was used instead of the M88. In 1989, an updated version of the S38 became the worldwide replacement for the M88. The M30B35LE is a SOHC engine which is based on the M88/1; this is sometimes referred to as the M90.

DesignEdit

BMW engineers used a DOHC valvetrain on a production engine for the first time on the M88, with the camshafts driven by a single-row timing chain.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> Kugelfischer fuel injection<ref name=projectM1 /> was used with individual throttle valves<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> and the distinctive six individual throttle bodies.

The construction is an aluminium cylinder head and a cast iron block.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> The bore is Template:Convert and the stroke is Template:Convert, resulting in a displacement of Template:Convert.

VersionsEdit

Engine code Power Torque Years Note
M88 Template:Cvt
at 6,500 rpm
Template:Convert
at 5,000 rpm
1978-1981 BMW M1
M88/1 Template:Cvt
at 9,000 rpm
Template:Convert
at 7,000 rpm
1979-1980 Gr.4 Procar
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up to Template:Cvt
at 9,000 rpm
Template:Convert at 7,000 rpm<ref>{{#invoke:citation/CS1|citation CitationClass=web

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M88/3 Template:Cvt
at 6,500 rpm
Template:Convert
at 4,500 rpm
1983–1989 M635 CSi, M5, 745i (South Africa only)
M30B35LE/M90 Template:Cvt
at 5,200 rpm
Template:Convert
at 4,000 rpm
1978–1982 SOHC

M88Edit

File:BMW M1 Ausstellungsmotor.jpg
M88/1 with some parts replaced with Plexiglas for display purposes

The M88 was the original iteration of the engine and was fitted to the BMW M1. It produces Template:Cvt at 6,500 rpm and Template:Cvt at 5,500 rpm. A dry sump is used.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Applications:

  • 1978-1981 M1

M88/1Edit

For the BMW M1 Procar single-make series, the M88 engine was bored out marginally to reach Template:Convert. This racing version, called the M88/1, met the Group 4 regulations. This race engine produced Template:Cvt in Procar specifications. This version had forged pistons, sharper camshafts, bigger valves, as well as oil cooling for the transmission and rear differential.

Applications:

M88/2Edit

For Group 5 racing, the M88 engine was turbocharged and became known as the M88/2. It was downsleeved and had a shorter stroke to displace Template:Convert, which with the 1.4 turbo factor placed it in the 4.5-liter class. This race engine produced up to Template:Cvt.<ref name=carlust>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Applications:

M88/3Edit

File:BMW M88 3 Auspuffseite.JPG
M88/3 iteration used in the E24 M635CSi and E28 M5.

The M88/1 engine was modified for use in the E24 M635CSi and E28 M5 and was known as the M88/3.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> The Kugelfischer fuel injection was replaced with Bosch Motronic producing Template:Cvt at 6,500 rpm and Template:Cvt at 4,500 rpm.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> It has a compression ratio of 10.5:1.

The M88/3 was also fitted to the South African BMW 745i, due to packaging problems with the turbocharged M102 engine which was used in other markets.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Applications:

  • 1983-1989 E24 M635CSi
  • 1984-1987 E28 M5
  • 1984-1987 E23 745i (South Africa only)

Template:Anchor M30B35LEEdit

The M30B35LE is a lower performance, two-valve, SOHC version of the M88/1 engine, also known as the M90. It utilizes the same block as the M88 and maintains the same bore and stroke, but borrows its head from the BMW M30 engine family. Depending on year, this engine uses either Bosch Motronic or Bosch L-Jetronic as its engine management system.<ref name=projectM1>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> Typically identified by a white L painted on the block behind the oil filter housing and coolant water passages on the side of the block.

As sold in Europe and most other markets (except North America), this engine used a compression ratio of 9.3:1, did not have a catalytic converter, and produced Template:Cvt.

Applications:

See alsoEdit

  • BMW S14 - Four-cylinder engine based on the M88

ReferencesEdit

Template:Reflist

Template:BMW automotive petrol engines: 1960s to 1980s