Abstract: A method of operating an internal combustion engine system comprises introducing an oxygen containing gas and a fuel into a combustion chamber of an internal combustion engine; combusting the fuel to produce an exhaust gas; introducing the exhaust gas into a turbine of a turbocharger, wherein the turbine is a variable geometry turbine; recycling a portion of the exhaust gas exiting the turbine to a compressor of the turbocharger using an EGR valve; compressing the recycled portion of the exhaust gas and compressing the oxygen containing gas to produce a compressed gas; and introducing the compressed gas on an intake stroke of a piston into the engine and closing the intake valve either before the piston reaches an end of the inlet stroke or later to the piston reaching bottom dead center.

Abstract: A system is provided. The system includes an internal combustion engine having an intake manifold and an exhaust manifold. The system also includes a high pressure turbocharger having a variable geometry high pressure turbine drivingly coupled to a high pressure compressor, wherein the variable geometry high pressure turbine is driven by a first portion of exhaust gases from the exhaust manifold, wherein the high pressure compressor is configured to compress an intake air and to provide the compressed intake air to the intake manifold.

Abstract: In accordance with one aspect of the present technique, a method of reducing pollutant emissions from a compression-ignition engine is provided. The method includes adjusting timing of fuel injection into a combustion chamber of a piston-cylinder assembly of the compression-ignition engine. The method of adjusting timing of fuel injection includes indexing a drive mechanism intercoupling a camshaft to a crankshaft by at least one tooth away from a standard position. The method of adjusting timing of fuel injection further includes adjusting a pre-stroke of a plunger of a fuel injector assembly.