A system includes an internal combustion engine having a number of cylinders. At least one of the cylinders is a primary EGR cylinder that solely provides EGR flow during at least some operating conditions. Operation of the primary EGR cylinder is controlled separately from the other cylinders to reduce internal residuals in the primary EGR cylinder.

A system includes an internal combustion engine having a number of cylinders. At least one of the cylinders is a primary EGR cylinder that solely provides EGR flow during at least some operating conditions. Operation of the primary EGR cylinder is controlled separately from the other cylinders to reduce internal residuals in the primary EGR cylinder.

A valve train system for an internal combustion engine includes an exhaust valve moveable between an exhaust closed position and an exhaust open position. A camshaft includes a main exhaust lobe for moving the exhaust valve between the exhaust closed position and the exhaust open position for expelling exhaust constituents from the combustion chamber and an exhaust rebreath lobe for moving the exhaust valve between the exhaust closed position and the exhaust open position for allowing exhaust constituents into the combustion chamber. A two-step device is provided for transmitting motion from the camshaft to the exhaust valve and is switchable between a motion transmitting position and a motion preventing position such that the motion transmitting position allows motion to be transmitted from the exhaust rebreath lobe to the exhaust valve and the motion preventing position prevents motion from being transmitted from the exhaust rebreath lobe to the exhaust valve.

A valve train system for an internal combustion engine includes an exhaust valve moveable between an exhaust closed position and an exhaust open position. A camshaft includes a main exhaust lobe for moving the exhaust valve between the exhaust closed position and the exhaust open position for expelling exhaust constituents from the combustion chamber and an exhaust rebreath lobe for moving the exhaust valve between the exhaust closed position and the exhaust open position for allowing exhaust constituents into the combustion chamber. A two-step device is provided for transmitting motion from the camshaft to the exhaust valve and is switchable between a motion transmitting position and a motion preventing position such that the motion transmitting position allows motion to be transmitted from the exhaust rebreath lobe to the exhaust valve and the motion preventing position prevents motion from being transmitted from the exhaust rebreath lobe to the exhaust valve.

An ignition system includes an ignition coil with a primary winding and a secondary winding having a terminal for providing a high voltage (HV). An electrode arrangement of an igniter includes first and second HV electrodes coupled to the terminal of the secondary winding. The igniter also has at least one ground electrode. A first spark gap is defined between the first HV electrode and the at least one ground electrode, and a second spark gap is defined between the second HV electrode and the at least one ground electrode. A first capacitor is disposed in-line between the first HV electrode and the terminal of the secondary winding and a second capacitor disposed in-line between the second HV electrode and the terminal of the secondary winding of the ignition coil. The ignition system includes a driver module coupled to a terminal of the primary winding, for driving the ignition coil.

A computer control network is connected to a multiple-cylinder engine and implements aftertreatment temperature management. Processors are configured to determine an aftertreatment temperature-efficient air to fuel ratio that satisfies the sensed power output request, determine an air to fuel ratio adjustment, select an in-cylinder exhaust gas recirculation technique, select at least one EGR cylinder of the multiple-cylinder engine to implement the in-cylinder exhaust gas recirculation technique, and control the intake valves to open and the exhaust valves to close for the selected at least one EGR cylinder to adjust the oxygen and particulate content of the exhaust gas by applying at least a second compression stroke of the respective reciprocating piston of the at least one EGR cylinder to the exhaust gas to push the exhaust gas through to the intake manifold.

A computer control network is connected to a multiple-cylinder engine and implements aftertreatment temperature management. Processors are configured to determine an aftertreatment temperature-efficient air to fuel ratio that satisfies the sensed power output request, determine an air to fuel ratio adjustment, select an in-cylinder exhaust gas recirculation technique, select at least one EGR cylinder of the multiple-cylinder engine to implement the in-cylinder exhaust gas recirculation technique, and control the intake valves to open and the exhaust valves to close for the selected at least one EGR cylinder to adjust the oxygen and particulate content of the exhaust gas by applying at least a second compression stroke of the respective reciprocating piston of the at least one EGR cylinder to the exhaust gas to push the exhaust gas through to the intake manifold.

Methods and systems are provided for a prechamber. In one example, a system comprises a reservoir fluidly coupled to a prechamber and a compressor. The reservoir is configured to store boost air or residual gases.

One embodiment is a system comprising an engine including a dedicated EGR cylinder configured to provide EGR to the engine via an EGR loop, a non-dedicated cylinder, a plurality of injectors structured to inject fuel into the dedicated EGR cylinder and the non-dedicated EGR cylinder, and an electronic control system operatively coupled with the fueling system and the ignition system. The electronic control system is configured to evaluate engine operating parameters including an engine load and an engine speed. The electronic control system is responsive to variation of the engine operating parameters to control operation of the fueling system to vary combustion in the at least one dedicated cylinder between rich of stoichiometric and stoichiometric.

One embodiment is a system comprising an engine including a dedicated EGR cylinder configured to provide EGR to the engine via an EGR loop, a non-dedicated cylinder, a plurality of injectors structured to inject fuel into the dedicated EGR cylinder and the non-dedicated EGR cylinder, and an electronic control system operatively coupled with the fueling system and the ignition system. The electronic control system is configured to evaluate engine operating parameters including an engine load and an engine speed. The electronic control system is responsive to variation of the engine operating parameters to control operation of the fueling system to vary combustion in the at least one dedicated cylinder between rich of stoichiometric and stoichiometric.