Subaru Introduces Line of Electronic Fuel Injection (EFI) Engines

March 18, 2009
In addition to its current line of engines, Subaru offers a new line of electronic fuel injection (EFI) engines, which are ideally suited for use with a variety of equipment, including welders, generators, pressure washers and lawnmowers. The line includes two models, the EH72 V-Twin and EH72 UTV, both of which are designed to reduce fuel consumption and emissions, while providing fast, easy starts in a wide range of ambient temperatures. Used in car engines since the 1980’s, EFI technology has been applied by Subaru to its small, air-cooled industrial engines. The EFI engines run on an open-loop system, which utilizes an electronic control unit (ECU). Using several different sensors that are able to accurately detect manifold pressure, ambient temperature and throttle position, the ECU is constantly relaying information to the injector, which is then able to deliver the proper air-to-fuel ratio. The result of this continuous relay of information is an engine that is always running at an optimal level, resulting in better fuel economy and emissions control. Allowing for differences in operating speed, applications and fuel type, the estimated fuel economy improvements are 11 to 25 percent over that of a similar carbureted engine. Additionally, exhaust emissions are reduced by more than 20 percent. Easier starts are another advantage of the EFI engines. Fuel volume is closely controlled to provide fast starts in a variety of ambient temperatures. Excellent response and acceleration is delivered from the initial start up, eliminating the need for a choke. Altitude changes pose no threat to the EFI engine’s operation, thanks to precise oxygen level detection from the ECU sensors. The system is able to identify changes in altitude and instantly adjusts the air-to-fuel ratio to make it ideal for the current location. Maximum fuel economy and power in any altitude is achieved throughout the entire power range from low idle to full power. Both models are available in a 653 cc or 720 cc configuration, with power outputs ranging from 20- to 27-horsepower. The engines feature a two-barrel manifold with a fuel injector for each cylinder. This allows each cylinder to operate independently of the other, which aids in fuel optimization and also in improving the engine’s efficiency and performance. For applications that require a smaller, more compact engine, the EH72 UTV engine is available in a low-profile design for both the 653 cc and 720 cc configurations. The engines are also available in non-EFI carbureted versions. Similar to the EFI engines, the carbureted versions utilize independently operating cylinders for fuel optimization and improved engine efficiency and performance. • Class V-Twin cylinder • Shaft Horizontal • Cylinders 2 • Displacement 720 • Cycles 4 • Fuel Gasoline • Max HP/RPM (Gross HP) 25.0/3600 • Max KW/RPM 18.6/3600 • Max Torque ftlbs/RPM 39.6/2500 • Max Nm/RPM 53.6/2500 • Bore x Stroke mm 84 x 65 • Compression Ratio 8.3:1 • Starter Electric • Dry Weight lbs 101 • Dry Weight kg 46 • Length inches (mm) 317 • Width inches (mm) 477 • Height inches (mm) 475 • Oil Capicity Fl oz (ltrs) 57.46