An exhaust valve rocker arm for an exhaust valve rocker arm assembly operable in a combustion engine drive mode and an engine braking mode, and configured to selectively open first and second exhaust valves, includes a body defining an aperture to receive a rocker shaft such that the body is rotatable about the rocker shaft, a bore defined in the body, and a rotating stepped engine brake capsule disposed in the bore and having a castellation mechanism. The rotating stepped engine brake capsule is movable between a locked, engine brake active position and an unlocked, engine brake inactive position.

A system for actuating one or more engine valves comprises a lost motion assembly including locking elements to selectively lock and unlock a locking mechanism disposed within a valve train such that motions may be likewise selectively applied to, or prevented from being applied to, one or more engine valves. In an embodiment, the locking elements comprise wedges having at least one wedge inclined surface defined according to a cone frustum and configured to engage an outer recess formed in a housing, the outer recess comprising an outer recess inclined surface also defined according to the cone frustum. The device may comprise a locking mechanism disposed within a housing bore in the housing and a snubber also disposed in the housing bore. Furthermore, the outer recess may be configured to permit movement of the locking element along a longitudinal axis of the housing bore.

A system for actuating one or more engine valves comprises a lost motion assembly including locking elements to selectively lock and unlock a locking mechanism disposed within a valve train such that motions may be likewise selectively applied to, or prevented from being applied to, one or more engine valves. In an embodiment, the locking elements comprise wedges having at least one wedge inclined surface defined according to a cone frustum and configured to engage an outer recess formed in a housing, the outer recess comprising an outer recess inclined surface also defined according to the cone frustum. The device may comprise a locking mechanism disposed within a housing bore in the housing and a snubber also disposed in the housing bore. Furthermore, the outer recess may be configured to permit movement of the locking element along a longitudinal axis of the housing bore.

A method to reduce during the start of an engine undesired emissions from the engine, where an SCR catalytic converter for the cleaning of exhaust gases is arranged in an exhaust passage at the engine. The method includes controlling the dosage of fuel to the engine with a certain delay relative to what is the case during essentially optimal combustion in order to reduce the development of heat that results from the combustion of fuel through non-optimal combustion. Also a computer program product comprising program code to implement a method of reducing emissions. Also an arrangement to reduce during the start of an engine undesired emissions from the engine and a motor vehicle that is equipped with the arrangement.

A method to reduce during the start of an engine undesired emissions from the engine, where an SCR catalytic converter for the cleaning of exhaust gases is arranged in an exhaust passage at the engine. The method includes controlling the dosage of fuel to the engine with a certain delay relative to what is the case during essentially optimal combustion in order to reduce the development of heat that results from the combustion of fuel through non-optimal combustion. Also a computer program product comprising program code to implement a method of reducing emissions. Also an arrangement to reduce during the start of an engine undesired emissions from the engine and a motor vehicle that is equipped with the arrangement.

An engine braking system includes engine braking actuators for adjusting exhaust valve timings to engine braking timings in a cylinder-number braking mode. The system further includes an engine braking controller coupled to a control switch that produces a request indicating a requested cylinder-number braking mode. The engine braking controller is structured to transition exhaust valves to the engine braking timings, determine a control term to adjust intake air pressure for varying a braking power of the engine, and to adjust geometry of an exhaust turbine based on the control term. An adjusted speed of a compressor rotated by the exhaust turbine provides a change to intake air pressure that adjusts the braking power of the engine. Different levels of braking power are provided within different cylinder-number braking modes.

An engine braking system includes engine braking actuators for adjusting exhaust valve timings to engine braking timings in a cylinder-number braking mode. The system further includes an engine braking controller coupled to a control switch that produces a request indicating a requested cylinder-number braking mode. The engine braking controller is structured to transition exhaust valves to the engine braking timings, determine a control term to adjust intake air pressure for varying a braking power of the engine, and to adjust geometry of an exhaust turbine based on the control term. An adjusted speed of a compressor rotated by the exhaust turbine provides a change to intake air pressure that adjusts the braking power of the engine. Different levels of braking power are provided within different cylinder-number braking modes.

A method for intelligent active engine braking using full authority active fuel management based on vehicle speed and brake pedal position. The method includes determining if the tow mode of the vehicle has been selected and enables all engine cylinders to ensure maximum engine braking capacity is available. When vehicle tow mode is not selected then the method varies engine braking capacity by disabling one or more cylinders based on the vehicle speed and brake pedal position.

An engine brake controller may obtain a performance characteristic of an engine. The engine brake controller may determine, based on the performance characteristic of the engine, that engine braking is enabled to control the engine. The engine brake controller may monitor a set of operating parameters of the engine. The engine brake controller may determine that operating values of the set of operating parameters satisfy corresponding thresholds of the set of operating parameters. The engine brake controller may determine, based on the operating values satisfying the corresponding thresholds, an engine braking configuration associated with activating engine braking of a set of cylinders of the engine. The set of cylinders may be a proper subset of a total quantity of cylinders of the engine. The engine brake controller may cause the engine braking to be applied to the set of cylinders to increase a temperature of exhaust gas from the engine.

An engine brake controller may obtain a performance characteristic of an engine. The engine brake controller may determine, based on the performance characteristic of the engine, that engine braking is enabled to control the engine. The engine brake controller may monitor a set of operating parameters of the engine. The engine brake controller may determine that operating values of the set of operating parameters satisfy corresponding thresholds of the set of operating parameters. The engine brake controller may determine, based on the operating values satisfying the corresponding thresholds, an engine braking configuration associated with activating engine braking of a set of cylinders of the engine. The set of cylinders may be a proper subset of a total quantity of cylinders of the engine. The engine brake controller may cause the engine braking to be applied to the set of cylinders to increase a temperature of exhaust gas from the engine.