Editing Citroën SM (section)

==Engines==<!-- This section is linked from [[PRV engine]] -->
[[File:1969 Giulio Alfieri and SM V6 engine.jpg|right|thumb|160px|[[Giulio Alfieri]] and SM engine in May 1969]]
The SM was sold with a small, lightweight engine in various forms, designed from scratch by [[Giulio Alfieri]] but capable of being assembled on the existing tooling for the [[Maserati V8 engine]]. Because of this, the engine sported an unusual 90° angle between cylinder banks – a trait shared with the later [[PRV engine|PRV V6]]. It was a very compact and innovative design that allowed the use of just one pattern for the cylinder heads and an intermediate shaft extended out to drive the auxiliaries.

The engine was aluminum, weighing just {{cvt|140|kg|lb|0}}, and was always mounted [[mid-engine design|behind the front axle]].<ref>{{cite web|url=http://www.maserati-alfieri.co.uk/menotti12.htm|title=Maserati Engines II|work=maserati-alfieri.co.uk}}</ref>

{|class="wikitable" style="text-align:center; font-size:85%;"
|-style="background:#DCDCDC; font-weight:bold"
| Model
| Serial number
| Engine
| Displacement<br />cc
| Fuel supply
| Power <br /> (DIN)
| Transmission/<br />N° gears
| Weight
| Top Speed
| Years of<br />production
| Number produced
|-
|'''SM 2.7'''||type SB||C114-1||rowspan="3"|2,670|| 3 [[Weber carburetor]]s <br /> 42DCNF||rowspan="2"|{{cvt|170|PS|kW hp|0}}||M/5||{{Convert|1450|kg|0|abbr=on}}||{{Convert|220|km/h|0|abbr=on}}||1970–72||7.133
|-
|'''SM 2.7 Automatique'''||type SB||C114-1|||3 [[Weber carburetor]]s <br /> 42DCNF||A/3||{{Convert|1480|kg|0|abbr=on}}||{{Convert|205|km/h|0|abbr=on}}||1972||675
|-
|'''SM 2.7 Injection'''||type SC||C114-3||Electronic Injection <br />[[Robert Bosch GmbH|Bosch]] D-Jetronic||{{Convert|178|PS|kW hp|0|abbr=on}}||M/5||{{Convert|1490|kg|0|abbr=on}}||{{Convert|228|km/h|0|abbr=on}}||1972–75||3.500
|-
|'''SM 3.0'''||type SD||C114-11||rowspan="2"|2,965||3 [[Weber carburetor]]s <br /> 42DCNF||rowspan="2"|{{cvt|180|PS|kW hp|0}}||M/5||{{Convert|1450|kg|0|abbr=on}}||{{Convert|225|km/h|0|abbr=on}}||1973||600
|-
|'''SM 3.0 Automatique'''||type SD||C114-11||3 [[Weber carburetor]]s <br /> 42DCNF||A/3||{{Convert|1480|kg|0|abbr=on}}||{{Convert|205|km/h|0|abbr=on}}||1973–75||1.012
|}

The size of the 2.7&nbsp;L engine was limited by French [[Tax horsepower|puissance fiscale]] taxation, which made large displacement vehicles too expensive to sell in any quantity in [[France]].<ref name="webmaster"/>
[[File:Citroen SM Twin Turbo.JPG|thumb|Twin Turbo V6 SM developed by ''SM World'' in [[Los Angeles]], California – achieved {{convert|325|km/h|abbr=on}} at [[Bonneville Salt Flats]] ]]
One SM had a Maserati V8 motor – this was a heavily used test bed developed by [[Maserati]] for the 1974 [[Maserati Quattroporte II]].<ref name="autoweek.com">{{cite web|url=http://autoweek.com/article/1974-citron-sm-v8-mystery-no-more|title=1974 Citron SM V8: A Mystery No More – Autoweek|work=autoweek.com|date=27 September 2010}}</ref> Despite developing {{convert|260|HP|abbr=on|order=flip}}, the car required relatively modest adjustments, and the performance made the SM into a true sporting car.<ref>{{cite web|url=http://www.autotraderclassics.com/car-article/The+lost+prototype+Reborn+_+Citroen+SM+V8-84209.xhtml|title=AutoTraderClassics.com – Article The lost prototype Reborn – Citroen SM V8|work=autotraderclassics.com}}</ref>

One SM had a V6 twin Turbo – developed by specialist Jerry Hathaway (''SM World'') for [[land speed record]] testing at [[Bonneville Salt Flats]] – achieving {{convert|202|mph|order=flip|abbr=on}}.<ref name="lefigaro.fr"/>

Smooth shifting 5-speed [[manual transmission]]s were fitted to most SMs.<ref name="drive-my.com" /> A 3-speed [[Borg-Warner 35 transmission|Borg Warner]] fully [[automatic transmission]] was an option in North America in 1972–73, and in Europe 1974–75.

The engine was also used in the [[Maserati Merak]] from 1972 to 1982. Later versions of the Merak ''SS'' had much larger valves and developed {{convert|220|HP|||abbr=on|order=flip}}. The [[Ligier JS2]] [[sports car]] also used this [[V6 engine]]. The final SMs were produced in the [[Ligier]] factory in [[Vichy]].

Under new ownership, [[Maserati]] developed the 1981 [[Maserati Biturbo|Biturbo]] model, by applying [[turbocharging]] to this engine, and sold 40,000 units.