The Mitsubishi 3B2 engine is a family of all-alloy three cylinder engines developed by Mitsubishi Motors, first produced in December 2005 at the company's Mizushima powertrain facility in Kurashiki, Okayama,"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 kei car. All engines developed within this family have aluminum cylinder block and head, double overhead camshafts, four valves per cylinder, and MIVEC continuous variable valve timing."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'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 manifolds 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. Bore pitch 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 engines, meaning fuel consumption 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 Production 2006-2013 2013 - 2020 Configuration Three cylinder 45° inclined Three cylinder upright Valve Train chain driven DOHC Aspiration naturally aspirated Displacement Bore x stroke Compression ratio 10.8:1 10.9:1 or 12:1 Fuel type Regular unleaded gasoline Peak power at 7000 rpm at 6500 rpm Peak torque at 4000 rpm at 5000-5500 rpm Applications: 2006 - 2013 Mitsubishi i 2013 - 2019 Mitsubishi eK 2013 - 2019 Nissan Dayz 2014 - 2020 Mitsubishi eK Space 2014 - 2020 Nissan Dayz Roox
3B20T Production 2006-2013 2013 - 2020 Configuration Three cylinder 45° inclined Three cylinder upright Valve Train chain driven DOHC Aspiration turbocharger and Intercooler Displacement Bore x stroke Compression ratio 8.8:1 9.0:1 Fuel type Regular unleaded gasoline Peak power at 6000 rpm at 6000 rpm Peak torque at 3000 rpm at 3000 rpm Applications: 2006 - 2013 Mitsubishi i 2013 - 2019 Mitsubishi eK 2013 - 2019 Nissan Dayz 2014 - 2020 Mitsubishi eK Space 2014 - 2020 Nissan Dayz Roox
3B21 This engine is also known as Mercedes-Benz M132 E10 Engine Type 3B21 3B21 3B21 (North America) Configuration Three cylinder, 45° inclined, DOHC Aspiration naturally aspirated Displacement Bore x stroke Compression ratio 10.0:1 Fuel type 95 Octane Premium unleaded gasoline Peak power at 5800 rpm at 5800 rpm at 6000 rpm Peak torque at 3000 rpm at 4500 rpm at 3000 rpm Applications: 2007 - 2014 Smart Fortwo
3B21T This engine is also known as Mercedes-Benz M132 E10 AL Engine Type 3B21T 3B21T (Brabus) 3B21T (Brabus) Configuration Three cylinder, DOHC Aspiration turbocharger and Intercooler Displacement Bore x stroke Peak power at 5250 rpm at 5500 rpm at 6000 rpm Peak torque at 3250 rpm at 3500 rpm at 2500 - 3600 rpm Applications: 2007 - 2014 Smart Fortwo
See also List of Mitsubishi engines
References