Air inlet system for an internal combustion engine

An air inlet system (10) for an internal combustion engine (200) is provided. The air- inlet system comprises an air intake port (20), an air output port (30) for providing air for a combustion chamber (202) of the combustion engine (200), and a turbine (40). The turbine (40) is situated in between the air intake port (20) and the air output port (30) for turning kinetic energy from the air intake port (20) to the air output port (30) into mechanical energy. The turbine (40) comprises at least one impeller blade (44) and multiple adjustable vanes (48) for controlling an air flow resistance of the turbine (40), the adjustable vanes (48) being configurable in at least a first position, a second position and a third position. In the first position, two adjacent adjustable vanes (48) form a nozzle (37) for directing the airstream towards the impeller blade (44). In the second position, the two adjacent adjustable vanes (48) form a narrower nozzle (37) for directing the airstream towards the impeller blade (44). In the third position, the two adjacent adjustable vanes (48) are essentially in one line, such that a flow area for the airstream between said adjacent adjustable vanes (48) is minimal.