# BMW M40
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> Markdown URL: https://mediated.wiki/source/BMW_M40.md
> Source: https://en.wikipedia.org/wiki/BMW_M40
> Source revision: 1347952073
> License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/)
{{Infobox automobile engine
|name=BMW M40 engine
|manufacturer=[BMW](/source/BMW)
|production=1987–1994
|configuration=[Naturally aspirated](/source/Naturally_aspirated) [straight-4](/source/Straight-four_engine)
|displacement= {{unbulleted list | {{convert|1596|cc|L|1|abbr=on|disp=flip}} | {{convert|1796|cc|L|1|abbr=on|disp=flip}} }}
|bore={{convert|84|mm|in|2|abbr=on}}
|stroke={{convert|72|mm|in|2|abbr=on}}
{{convert|81|mm|in|2|abbr=on}}
|predecessor=[BMW M10](/source/BMW_M10)
|successor=[BMW M43](/source/BMW_M43)
|valvetrain = [SOHC](/source/Overhead_camshaft)
|fueltype=[Petrol](/source/Petrol_engine)
|fuelsystem=[Fuel injection](/source/Fuel_injection)
|coolingsystem=[Water cooled](/source/Radiator_(engine_cooling))
|image = M40B16.JPG
|management=[Bosch](/source/Robert_Bosch_GmbH) [Motronic 1.3](/source/Motronic) or [1.7](/source/Motronic)
|block=[Cast iron](/source/Cast_iron)
|head=[Aluminium](/source/Aluminium)
}}
The '''BMW M40''' is an [SOHC](/source/SOHC) [straight-four](/source/straight-four) [petrol engine](/source/petrol_engine) which was produced from 1987 to 1994.[{{cite web |title=BMW M40B18 automotive engine |url=https://bmw-grouparchiv.de/research/detail/index.xhtml?id=3942278 |website=bmw-grouparchiv.de |accessdate=15 August 2019 |archive-date=5 November 2018 |archive-url=https://web.archive.org/web/20181105045345/https://bmw-grouparchiv.de/research/detail/index.xhtml?id=3942278 |url-status=dead }}][{{cite web |title=BMW M40B16 automotive engine |url=https://bmw-grouparchiv.de/research/detail/index.xhtml?id=3942253 |website=bmw-grouparchiv.de |accessdate=15 August 2019 |archive-date=5 November 2018 |archive-url=https://web.archive.org/web/20181105045108/https://bmw-grouparchiv.de/research/detail/index.xhtml?id=3942253 |url-status=dead }}] It served as [BMW](/source/BMW)'s base model four-cylinder engine and was produced alongside the higher performance [BMW M42](/source/BMW_M42) DOHC four-cylinder engine from 1989 onwards.
Compared with its M10 predecessor, the M40 uses a belt-driven camshaft,[{{cite web|title=M40 - E30 Zone Wiki|url=http://www.e30zone.net/e30zonewiki/index.php/M40|website=www.e30zone.net|accessdate=27 January 2017|language=en|archive-date=4 October 2008|archive-url=https://web.archive.org/web/20081004061209/http://www.e30zone.net/e30zonewiki/index.php/M40|url-status=dead}}] and hydraulic tappets. Like the M10, the M40 uses an iron block and an aluminium head. Fuel injection for the E30 versions is [Bosch Motronic 1.3](/source/Motronic),[{{cite web|title=3' E30 318i Uncoded DME control unit|url=http://www.realoem.com/bmw/enUS/showparts?id=AF51-EUR-04-1990-E30-BMW-318i&diagId=12_0856#12141734100|website=www.realoem.com|accessdate=1 February 2017}}] and the E36 versions use [Bosch Motronic 1.7](/source/Motronic).[{{cite web|title=3' E36 318i Uncoded DME control unit|url=http://www.realoem.com/bmw/enUS/showparts?id=CA31-EUR-03-1990-E36-BMW-318i&diagId=12_1979#12140028569|website=www.realoem.com|accessdate=1 February 2017|date=27 October 1975}}][{{cite web |author=Roy McNeill, Copyright BMW World 1999–2005 |url=http://www.usautoparts.net/bmw/engines/4cyl.htm |title=BMW World – 4-Cylinder Engines |publisher=Usautoparts.net |accessdate=2012-05-29 |url-status=dead |archiveurl=https://web.archive.org/web/20140302135705/http://www.usautoparts.net/bmw/engines/4cyl.htm |archivedate=2014-03-02 }}]
Following the introduction of the [BMW M43](/source/BMW_M43) engine in 1991, the M40 began to be phased out.
== Versions ==
{|class="wikitable sortable"
|-
! Version !!Displacement!!Power!!Torque!!Year
|-
|'''M40B16-'''
[E30](/source/BMW_3_Series_(E30)) version || rowspan=2| {{cvt|1596|cc|cuin|1}} || {{cvt|73|kW|PS hp|0}}
at 5,500 rpm || {{cvt|141|Nm|lbft|0}}
at 4,250 rpm ||1987
|-
|'''M40B16-'''
[E36](/source/BMW_3_Series_(E36)) version ||{{cvt|75|kW|PS hp|0}}
at 5,500 rpm || {{cvt|143|Nm|lbft|0}}
at 4,250 rpm ||1991
|-
|'''M40B18-'''
E30 version || rowspan=2| {{cvt|1796|cc|cuin|1}} || {{cvt|83|kW|PS hp|0}}
at 5,500 rpm || {{cvt|162|Nm|lbft|0}}
at 4,250 rpm||1987
|-
|'''M40B18-'''
E36 version || {{cvt|85|kW|PS hp|0}}
at 5,500 rpm || {{cvt|165|Nm|lbft|0}}
at 4,250 rpm ||1991
|}
== M40B16 ==
The M40B16 is a {{convert|1596|cc|cuin|1|abbr=on}} version of the M40, which has a bore of {{convert|84|mm|in|1|abbr=on}} and a stroke of {{convert|72|mm|in|1|abbr=on}}.[{{cite web|title=BMW M40 and M43 Four Cylinder Engines|url=http://www.unixnerd.demon.co.uk/m40.html|website=www.unixnerd.demon.co.uk|accessdate=10 February 2017|archive-date=28 September 2015|archive-url=https://web.archive.org/web/20150928214048/http://www.unixnerd.demon.co.uk/m40.html|url-status=dead}}] It produces {{Convert|73|kW|0|abbr=on}} and {{convert|105|lbft|Nm|0|abbr=on|order=flip}}.[{{cite web|url=http://www.bmwheaven.com/database/engine.php?type=M40 |title=BMW Heaven Specification Database | Engine specifications for M40 engines |website=www.bmwheaven.com |date= |accessdate=2012-05-29}}]
Applications:
*1988–1994 [316i (E30)](/source/BMW_3_Series_(E30))
*1990–1994 [316i (E36)](/source/BMW_3_Series_(E36))
*1992–1993 [Bertone Freeclimber 2](/source/%3Ait%3ABertone_Freeclimber_2)
== M40B18 ==
The M40B18 is a {{cvt|1796|cc|cuin|1}} version of the M40, which has a bore of {{cvt|84|mm|in|1}} and a stroke of {{cvt|81|mm|in|1}}.