The Mitsubishi 3B2 engine is a family of all-alloy three cylinder

engines An engine or motor is a machine designed to convert one or more forms of energy into mechanical energy. Available energy sources include potential energy (e.g. energy of the Earth's gravitational field as exploited in hydroelectric power ...

developed by

Mitsubishi Motors is a Japanese multinational automobile manufacturer headquartered in Minato, Tokyo, Japan.Kurashiki, Okayama is a historic city located in western Okayama Prefecture, Japan, sitting on the Takahashi River, on the coast of the Inland Sea. As of March 31, 2017, the city has an estimated population of 483,576 and a population density of 1,400 persons per ...

,"Newly Developed Three-Cylinder MIVEC Engine"
, Yukihiro Ryugo, Hiroaki Miwa, ''Mitsubishi Motors Technical Review'', 2006, no.18, pp.95–97 for introduction in their 2006

Mitsubishi i The is a kei car from automaker Mitsubishi Motors, first released in January 2006, twenty eight months after its debut at the Frankfurt Motor Show#2003, 2003 Frankfurt Motor Show. It is the first four-door automobile since the 1960s to employ ...

kei car Kei car (or , kanji: , "light automobile", ), known variously outside Japan as Japanese city car or Japanese microcar, is the Japanese vehicle category for the smallest highway-legal passenger cars with restricted dimensions and engine capacit ...

''. All engines developed within this family have aluminum cylinder block and head,

double overhead camshaft An overhead camshaft (OHC) engine is a piston engine where the camshaft is located in the cylinder head above the combustion chamber. This contrasts with earlier overhead valve engines (OHV), where the camshaft is located below the combustion cha ...

s, four valves per cylinder, and ''

MIVEC MIVEC (Mitsubishi Innovative Valve timing Electronic Control system) is the brand name of a variable valve timing (VVT) engine technology developed by Mitsubishi Motors. MIVEC, as with other similar systems, varies the timing of the intake and ex ...

continuous variable valve timing Continuity or continuous may refer to: Mathematics * Continuity (mathematics), the opposing concept to discreteness; common examples include ** Continuous probability distribution or random variable in probability and statistics ** Continuous g ...

."Development of Mitsubishi “i” Powertrain"
, Hirofumi Higashi, Kuniaki Kaihara, Hideki Miyamoto, Masayuki Takagaki, Kazuteru Kurose, Satoshi Yoshikawa, Hideo Nakai, Masayuki Yamashita, ''Mitsubishi Motors Technical Review'', 2004, no.16, pp.45–50 The 3B20 was designed with the " rear midship" layout in mind but is not limited to that. The basic dimensions chosen reduced the powerplant's height, the

cylinder block In an internal combustion engine, the engine block is the structure which contains the cylinders and other components. In an early automotive engine, the engine block consisted of just the cylinder block, to which a separate crankcase was attac ...

's structure was simplified, a timing chain was adopted, modularized components were used for the oil and water pumps, engine mounts, and fuel system. The aluminum construction and lightweight parts and materials in the

manifold In mathematics, a manifold is a topological space that locally resembles Euclidean space near each point. More precisely, an n-dimensional manifold, or ''n-manifold'' for short, is a topological space with the property that each point has a n ...

s helped reduce the weight of the engine by 20 percent compared with its iron-block '' 3G83'' predecessor, while gains were also seen in torque, fuel economy and

emissions Emission may refer to: Chemical products * Emission of air pollutants, notably: **Flue gas, gas exiting to the atmosphere via a flue ** Exhaust gas, flue gas generated by fuel combustion ** Emission of greenhouse gases, which absorb and emit rad ...

Bore pitch Bore pitch is the distance between the centerline of a cylinder bore to the centerline of the next cylinder bore adjacent to it in an internal combustion engine. It's also referred to as the "mean cylinder width", "bore spacing", "bore center dis ...

is 80 mm. The preliminary version of the engine was first seen in the "i" Concept test car introduced in 2003, and used Mitsubishi's '' Smart Idling'' system which turns off the engine automatically when the vehicle is stationary, and can restart it within 0.2 seconds."Development of “i” Concept Test Car for 2003 IAA and 2003 Tokyo Motor Show"
, Yoshinaka Kawakami, Takanori Yoshii, ''Mitsubishi Motors Technical Review'', 2004 no.16, pp.29-50 So equipped, Mitsubishi claimed the prototype was capable of fulfilling the "three litre initiative" for

gasoline Gasoline (; ) or petrol (; ) (see ) is a transparent, petroleum-derived flammable liquid that is used primarily as a fuel in most spark-ignited internal combustion engines (also known as petrol engines). It consists mostly of organic co ...

, meaning

fuel consumption A fuel is any material that can be made to react with other substances so that it releases energy as thermal energy or to be used for work. The concept was originally applied solely to those materials capable of releasing chemical energy but ...

of no more than . The larger capacity of the development engine was outside the limits of the ''kei'' class in Japan and was introduced in the second generation of the smart fortwo."Mitsubishi Motors and smart sign agreement on engine supply"
Mitsubishi Motors press release, Tokyo, October 28, 2005

Specifications

3B20

Applications: * 2006 - 2013

* 2013 - 2019

Mitsubishi eK The Mitsubishi eK is a kei car series from Mitsubishi Motors, based on the long-running Minica, and first introduced on October 11, 2001. According to the company, the "''eK''" name stands for "excellent ''keijidōsha''" or "excellent minicar".< ...

* 2013 - 2019

Nissan Dayz The Mitsubishi eK is a kei car series from Mitsubishi Motors, based on the long-running Minica, and first introduced on October 11, 2001. According to the company, the "''eK''" name stands for "excellent ''keijidōsha''" or "excellent minicar". ...

* 2014 - 2020 Mitsubishi eK Space * 2014 - 2020 Nissan Dayz Roox

3B20T

Applications: * 2006 - 2013

* 2013 - 2019

* 2014 - 2020 Mitsubishi eK Space * 2014 - 2020 Nissan Dayz Roox

3B21

This engine is also known as

Mercedes-Benz M132 Mercedes-Benz (), commonly referred to as Mercedes and sometimes as Benz, is a German luxury and commercial vehicle automotive brand established in 1926. Mercedes-Benz AG (a Mercedes-Benz Group subsidiary established in 2019) is headquartere ...

E10 Applications: * 2007 - 2014 Smart Fortwo

3B21T

This engine is also known as

E10 AL Applications: * 2007 - 2014 Smart Fortwo

References

{{Mitsubishi Motors technologies 3B2 Straight-three engines Gasoline engines by model

Specifications

3B20

3B20T

3B21

3B21T

See also

References