A PISTON FOR RECIPROCATING WITHIN A CYLINDER IN AN INTERNAL COMBUSTION ENGINE

A piston having a piston body with an upper end opposite a lower end, between which a center axis extends. The piston body includes a piston bowl having a piston bowl surface with a half section profile that includes a central bottom portion and a target side wall that extends between first and second separation cliffs. The central bottom portion extends radially at a central slope from the center axis to the first separation cliff. The target side wall extends at a slope that is different from the central slope. The target side wall receives fuel from a fuel injector at a spray angle that avoids contact with the first separation cliff for better fuel to air mixing to delay peak of combustion rate. The second separation cliff extends at a slope that directs the fuel plume away from and detaches from the second separation cliff for peak combustion.