FUEL-INJECTION TECHNOLOGY: EXTRAORDINARY POWER FOR PROFESSIONAL WORK
Fuel-injection technology makes engines lighter – and turns the STIHL MS 500i chainsaw into a powerhouse that professionals can rely on.
OXYGEN: THE KEY TO PERFORMANCE
The key requirement for fuel to run an engine is that it is in the right place at the right time – as well as always in the right quantity. Only a perfectly proportioned air-fuel mix from a fuel-injection system is designed for a quick, complete combustion, and enables the engine to operate to its full potential.
CARBURETOR VS. FUEL INJECTION
One way of providing the air-fuel mix in an engine is via a carburetor – fluctuations in altitude and temperature, a contaminated air filter, engine wear, and fuel quality can affect carburetor-only performance. If you’re a professional user and need optimal performance at various altitudes and temperature conditions, fuel injection is the answer. Fuel injection delivers fuel directly into the crankcase via an injection valve, or directly into the intake manifold. The injection pump keeps the fuel pressure constant, thereby ensuring that the fuel-injection valve provides exactly the right amount of fuel at any point during use.
Fuel injection is able to make these changes faster and allows for better acceleration, a simplified starting procedure (i.e. no choke), better power-to-weight ratio, etc.
THE STIHL MS 500i
The STIHL MS 500i chainsaw is the first chainsaw in the world to feature electronically controlled fuel injection. This chainsaw offers unparalleled performance thanks to the sensor-controlled fuel injection system in the engine that self-adjusts to always provide optimum power.
The innovative STIHL fuel-injection system – as well as the associated elimination of the carburetor and associated components – means the MS 500i is exceptionally lightweight with an excellent power-to-weight ratio.
Since the MS 500i has to be carried around, the fuel injection system must be smaller and lighter. The fuel pump is driven by the vacuum of the crankcase (i.e. no heavy electric fuel pump is needed). Since the fuel is injected into the vacuum of the manifold, only a low injection pressure is needed.
