Pre-combustion chamber of an internal combustion engine and method of operating the same

A pre-combustion chamber tip (76) of an internal combustion engine (10) exposed to high thermal and mechanical stress may be limited in space for arranging orifices (190, 290) fluidly communicating with a main combustion chamber (26) of the internal combustion engine. It is disclosed to efficiently use the limited space by providing a first group of orifices (190) extending at a first angle (±) with respect to a center axis (112) and a second group of orifices (290) extending at a second angle with respect to the center axis (112), wherein the outlets of the orifices are arranged at a first axial position (P1).