Open chamber diesel engine having a piston with recesses therein

In an open chamber diesel combustion engine having a cylinder and a piston movably disposed in said cylinder for reciprocal motion, a cylinder head secured over said cylinder and piston to form a combustion chamber, a pair of intake ports extending through said cylinder head and an intake valve operably mounted in each respective intake port for allowing air to be admitted into said combustion chamber, and a pair of exhaust ports extending through said cylinder head and an exhaust valve operably mounted in each respective exhaust port for allowing exhaust gases to exit said combustion chamber;

• the improvement characterized by:
• a multihole fuel injector nozzle tip having a plurality of radially diverging discharge orifices for spraying a plurality of fuel plumes into said combustion chamber;
• said piston having a plurality of recessed lobes circumferentially spaced about a central axis of said piston;
• each recessed lobe being substantially aligned with respect to a respective discharge orifice to receive a respective fuel plume;
• each intake and exhaust valve being aligned along its stem axis over a respective recessed lobe and sized to fit within said recessed lobe when in the partially open position and when said piston is at or near TDC.