Mitsubishi 3G8 engine

3G8
Overview
Manufacturer	Mitsubishi Motors
Production	1987–present
Combustion chamber
Cylinder block alloy	Cast iron

The Mitsubishi 3G8 engine is a range of three-cylinder powerplant from Mitsubishi Motors, introduced in the fifth generation of their Mitsubishi Minica kei car. In common with other contemporary engines in the class, it could be specified with many advanced technologies despite its diminutive size, including multi-valve cylinder heads and double overhead camshafts. The top-of-the-line Dangan ZZ variant was also the first kei car to benefit from turbocharging. In 1987 Mitsubishi was the first manufacturer to supercharge a kei vehicle, and in 1989 became the world's first production car to feature five valves per cylinder, ahead of similar developments by Bugatti, Audi, Ferrari and Toyota.

Its 3G81 three-cylinder engine has a displacement of 548 cubic centimetres and features three intake valves and two exhaust valves incorporated into each cylinder. The valves are controlled by twin overhead camshafts through roller cam followers on finger rockers with hydraulic automatic lash adjusters. Gasoline is electronically injected through triple-jet nozzles (also a technological first). The water-cooled turbocharger operates through an air-to-air intercooler. The ignition timing advance is also controlled electronically, and a knock-sensing system is included.

Originally a 550 cc engine, it was enlarged to 660 cc in 1990 following changes in the class regulations.

Displacement — 548 cc
Bore — 62.3 mm
Stroke — 60.0 mm
Fuel type — Unleaded regular gasoline

Displacement — 796 cc
Bore — 65.0 mm
Stroke — 80.0 mm
widdle Engine type — Inline three-cylinder SOHC 6 valves
Power — 33 kW (45 PS) at unknown rpm

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