AN EXPERIMENTAL LOW-PRESSURE GASOLINE DIRECT INJECTION SYSTEM FOR A SMALL CAPACITY TWO-STROKE ENGINE
Abstract
The Gasoline Direct Injection (GDI) requirement for special components had been limiting its
wider implementation. This work was carried out to obtain an experimental GDI system for a
small capacity two-stroke engine by using widely available Port Fuel Injection (PFI) components.
A low-pressure GDI system where a PFI injector was placed in position near scavenging port had
been obtained. The injection control system used throttle position and engine speed data to
determine the injection duration and the start of injection. The injection system’s fuel supply
characteristics was design to imitate the fuel supply characteristics of the engine’s carburetor that
was previously measured by varying load at constant throttle openings. The mass flow rate
measurement showed that the fuel injection system was able perform well at small throttle
opening and low engine speed but it needed more improvement to operate better at other
operating conditions.