Turbocharging a Crank-Case Scavenged and Direct-Injected Two-Stroke Engine for Snowmobile Applications

With the recent advancement in gasoline direct-injection technology for lightweight and high-specific power two-stoke engines, turbocharging a small crank-case scavenged GDI engine promises to be an effective way of increasing engine performance while maintaining the lowered emissions and increased fuel economy of GDI two-stroke engines. Along with increasing the power density, a variable geometry turbocharger should allow for an increase in low engine speed engine performance that will allow the engine to be operated at lower engine speeds providing quieter operation and decreased engine wear. Also presented is a method to increase throttle response and increase low speed torque through the use of a reed valve installed in the intake plenum.