Method of operating an IC engine and an IC engine for performing the method

An IC engine of the piston type, more particularly a reciprocating piston engine, with at least one combustion chamber (10), at least one inlet valve (14) with an inlet duct (36) coupled with said at least one combustion chamber, a charger (20) producing a continuous pressure associated with said inlet duct and with a storage space (28), an air control valve (34) coupled with said inlet duct between the storage space (28) and each inlet valve (14), said air control valve opens and closes in a way dependent on the ignition frequency of the associated combustion chambers (10), means for modifying the phase position of the inlet valve (14) and the air control valve (34), said means for modifying phase associated with said inlet valve and air control valve for shifting opening of said valves such that a supply of compressed air is concentrated at the start of opening of the inlet valve, compressed air is supplied during full opening of the inlet valve, or compressed air is concentrated at the closing of the inlet valve, and means for supplying non-compressed air to said at least one combustion chamber when said air control valve is closed, said means for supplying non-compressed air bypasses a compress branch of said duct including the charger, storage space and air control valve, and is coupled with said inlet duct, said means for supplying non-compressed air is able to be shut off by a valve means (38) when said air control valve is opened.