Abstract: A compressor (10) comprises counter rotating and intermeshing twisted rotors (18) and (20) disposed in a housing having an air intake plate (28) and an outlet (16). The outlet (16) has a first edge (60) and a second edge (70) which nm parallel with a length of the rotors (18) and (20) respectively. A gap (62) is formed in the outlet near a junction of the edges (60) and (70). Air which is compressed by the rotors (18) and (20) is able to bleed through the gap (62) in advance of trailing edges of lobes of at least one of the rotors (18) passing its corresponding edge (60). Also the rotors (18), (20) are arranged so that the trailing edge of a lobe of rotor (18) passes edge (60) before a trailing edge of a lobe of rotor (20) passes edge (70).

Abstract: A supercharging system (40) is disclosed which comprises a supercharging device (28) having at least one inlet port (42) and at least one outlet port (44), and at least one idle valve (30) in fluid communication with the supercharging device (28). The idle valve (30) is disposed adjacent the outlet port (44) and is arranged to selectively restrict fluid flow during use in a direction through the idle valve (30) towards the supercharging device (28). A corresponding supercharging kit and an internal combustion engine including a supercharging system are also disclosed.

Abstract: A compressor (10) comprises counter rotating and intermeshing twisted rotors (18) and (20) disposed in a housing having an air intake plate (28) and an outlet (16). The outlet (16) has a first edge (60) and a second edge (70) which nm parallel with a length of the rotors (18) and (20) respectively. A gap (62) is formed in the outlet near a junction of the edges (60) and (70). Air which is compressed by the rotors (18) and (20) is able to bleed through the gap (62) in advance of trailing edges of lobes of at least one of the rotors (18) passing its corresponding edge (60). Also the rotors (18), (20) are arranged so that the trailing edge of a lobe of rotor (18) passes edge (60) before a trailing edge of a lobe of rotor (20) passes edge (70).

Abstract: A supercharging system (40) is disclosed which comprises a supercharging device (28) having at least one inlet port (42) and at least one outlet port (44), and at least one idle valve (30) in fluid communication with the supercharging device (28). The idle valve (30) is disposed adjacent the outlet port (44) and is arranged to selectively restrict fluid flow during use in a direction through the idle valve (30) towards the supercharging device (28). A corresponding supercharging kit and an internal combustion engine including a supercharging system are also disclosed.