Effect of Intake Manifold Angle of Port-fuel Injection Retrofit-kit to the Performances of an SI Engine

Fuelling system is one of the crucial variables that must be focused on, in order to achieve good fuel efficiency and low engine out emissions. Fuel injection system seems a promising technology as a medium to supply suppressed fuel because of its high fuel delivery efficiency, enhanced fuel economy and reduced engine out emission. Port-fuel injection (PFI) system has been used widely on small four-stroke gasoline engine because of its simplicity compared to direct injection (DI) system. In this study, the effects of intake manifold angle of a PFI retrofit-kit to the engine performances and emission characteristics were investigated. Experimental works comprised wide-open throttle with variable dynamometer loads for two different angles: 90 degrees and 150 degrees. From this study, it was observed that 150 degrees was the best angle, which produced high brake power (BP) and brake mean effective pressure (BMEP), brake specific fuel consumption (BSFC) and hydrocarbon (HC) emission.