A spark-ignition reciprocating piston engine having at least one piston cylinder, at least one inlet port arranged at an end of the cylinder, an inlet valve located at the inlet port and being movable to open and close the inlet port, and an inlet conduit leading to the inlet port for feeding a fluid from a fuel feed to an inlet area of the inlet port, said engine comprising:
- a partition arranged within the inlet conduit and dividing the inlet conduit into at least two partial conduits over at least a portion of a length of the inlet conduit between the fuel feed and the inlet area, with at least one of the partial conduits being connected to the fuel feed, said partial conduits converging directly in front of the inlet port to form the inlet area, said partition being located within a plane that extends essentially transversely to an axis of the cylinder at least in the inlet area, and having an end edge facing the inlet area, said partition further having at least one deflecting portion that is movable to deflect a flow of the fluid on blow-by from the inlet conduit, through the inlet port, and into the cylinder;
- and
- controllable actuation means connected to said partition for changing a distance from the end edge to the inlet port.