The EF is an

automotive engine There are a wide variety of propulsion systems available or potentially available for automobiles and other vehicles. Options included internal combustion engines fueled by petrol, diesel, propane, or natural gas; hybrid vehicles, plug-in hybr ...

made by

Subaru is the automaker, automobile manufacturing division of Japanese transportation conglomerate (company), conglomerate Subaru Corporation (formerly known as Fuji Heavy Industries), the Automotive industry#By manufacturer, twenty-first largest aut ...

, introduced in 1984 for the Subaru Justy. It is a

water-cooled Cooling tower and water discharge of a nuclear power plant Water cooling is a method of heat removal from components and industrial equipment. Evaporative cooling using water is often more efficient than air cooling. Water is inexpensive and no ...

, straight-three,

four-stroke engine A four-stroke (also four-cycle) engine is an internal combustion (IC) engine in which the piston completes four separate strokes while turning the crankshaft. A stroke refers to the full travel of the piston along the cylinder, in either directi ...

with a belt-driven single overhead

camshaft A camshaft is a shaft that contains a row of pointed cams in order to convert rotational motion to reciprocating motion. Camshafts are used in piston engines (to operate the intake and exhaust valves), mechanically controlled ignition syst ...

, and a chain-driven

balance shaft Balance shafts are used in piston engines to reduce vibration by cancelling out unbalanced dynamic forces. The counter balance shafts have eccentric weights and rotate in the opposite direction to each other, which generates a net vertical force ...

. It has an alloy cylinder head and a closed deck iron

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

with a bore spacing of . The two-cylinder EK23 engine is closely related to the EF series, sharing the same bore spacing and overall design. The export market 665 cc EK42 motor even shares the bore and stroke of the EF10. It is the first Subaru engine to incorporate the displacement in its name, and the only iron block Subaru ever.

EF10

1.0-litre (997 cc) two valves per cylinder
Bore x Stroke: x Power: * at 5000 rpm/ at 3200 rpm with single barrel Hitachi carburetor and 9.5:1

compression ratio The compression ratio is the ratio between the maximum and minimum volume during the compression stage of the power cycle in a piston or Wankel engine. A fundamental specification for such engines, it can be measured in two different ways. Th ...

* at 6000 rpm/ at 3600 rpm with dual barrel Hitachi carburetor and 9.5:1

Usage: * Subaru Justy "J10" (limited to some European markets and Asia) * Subaru Libero "E10"

EF12

1.2-litre (1189 cc) three valves per cylinder
EF12engine

Bore x Stroke: x Power: * at 5200 rpm/ at 3600 rpm with two barrel Hitachi

carburetor A carburetor (also spelled carburettor or carburetter) is a device used by a gasoline internal combustion engine to control and mix air and fuel entering the engine. The primary method of adding fuel to the intake air is through the Ventu ...

and 9:1 compression ratio * at 5600 rpm/ at 3600 rpm with multi-port

fuel injection Fuel injection is the introduction of fuel in an internal combustion engine, most commonly automotive engines, by the means of a fuel injector. This article focuses on fuel injection in reciprocating piston and Wankel rotary engines. All c ...

and 9.1:1 compression ratio Usage: * Subaru Justy "J12" * Subaru Libero "E12" Power: * with multi-point

Usage: *Subaru Tutto (Taiwan)

External links

Subaru

Dusty's Justys

References

{{DEFAULTSORT:Subaru Ef Engine Subaru engines Straight-three engines