Gas intake device comprising an oriented masking element

A gas inlet device for a cylinder of an internal combustion engine, the gas inlet device comprising an inlet port, at least one inlet valve positioned within the inlet port, at least one valve seat of the inlet valve positioned at one end of the inlet port and facing toward the firing face of the cylinder, means for deflecting the gas to generate an aerodynamic movement of the gas within the cylinder about an axis perpendicular to an axis of the cylinder, at least one mask partially obstructing the end of the inlet port opening into the cylinder, wherein, on an intrados of the inlet port, the intrados of the inlet port being the lower face of the inlet port, an intersection between the inlet port and the valve seat forms a straight-line segment supported by a rectilinear generatrix forming an angle α of between 5 and 45° with respect to a plane parallel to the firing face of the cylinder and passing through a point of intersection between the inlet port and the valve seat, thereby forming a twist of the end of the inlet port, characterized in that a bore section of the inlet port has a rectangular shape with rounded corners, in that a midplane of the mask forms an angle γ about an axis of the inlet valve with respect to a midplane of the inlet port, such that γ=α+/−5°, the midplane of the mask being its plane of symmetry and the midplane of the inlet port being a plane sectioning the inlet port into two identical parts and containing the axis of the inlet valve.