Methods and systems are provided for improving turbocharger response in a boosted engine. In one example, a current turbocharger performance may be monitored, if meeting and operating in an optimum region for efficiency (e.g., on compressor and/or turbine maps), engine may be operated with a steady state exhaust valve opening (EVO) timing in an optimum position based on engine mapping (e.g., engine pumping work). Otherwise, the EVO timing may be advanced (opening earlier) to release more energy into the exhaust or retarded to release less, to move turbocharger to desired performance. By adjusting EVO timing to achieve desired turbocharger response and performance, faster response is achieved.

Methods and systems are provided for controlling an EGR valve and VGT vanes during engine braking. In one example, a method may include during an engine braking event in an engine, coordinating adjustments of both of a cross-sectional area of an inlet of a turbine and an opening of a valve of an exhaust gas recirculation (EGR) system to achieve a desired braking power and to maintain an exhaust system temperature above a threshold temperature during the engine braking event.

A rotary turbine bypass valve comprises a valve chamber and a valve rotor. The chamber is positioned at a junction of an inlet port, an outlet port and a bypass port. The inlet port is configured to receive exhaust gas, the outlet port is configured to fluidly communicate with a turbine inlet, and the bypass port is configured to fluidly communicate with an exhaust aftertreatment device. The rotor comprises a first and second recess, the first recess defining a primary flow passage, the second recess defining a secondary flow passage. The rotor is rotatable between a first position in which the rotor substantially blocks exhaust gas flow through the bypass port and a second position in which the rotor permits such. The secondary flow passage is configured to selectively permit fluid communication between the inlet port and the bypass port when the primary flow passage is partially blocked.

An exhaust-gas flap device, especially for the exhaust-gas flow of an internal combustion engine, has a flap pipe and a flap plate that is supported, in the interior of the flap pipe, on a pivot shaft that is rotatable about a pivot axis. The exhaust-gas flap device further includes a pivoting drive for the pivot shaft with a drive element. A coupling unit couples the drive element to the pivot shaft for conjoint rotation about the pivot axis. Vibration-damping material is arranged in the region of the coupling unit.

An exhaust-gas flap device, especially for the exhaust-gas flow of an internal combustion engine, has a flap pipe and a flap plate that is supported, in the interior of the flap pipe, on a pivot shaft that is rotatable about a pivot axis. The exhaust-gas flap device further includes a pivoting drive for the pivot shaft with a drive element. A coupling unit couples the drive element to the pivot shaft for conjoint rotation about the pivot axis. Vibration-damping material is arranged in the region of the coupling unit.

A compression-release engine brake system for effectuating a compression-release engine braking operation of an internal combustion engine. The compression-release system includes a lost motion exhaust rocker assembly including an exhaust rocker arm, an actuation device including an actuation piston and an actuation cavity, and a reset device including a reset check valve and a slider-piston. Hydraulic fluid in the exhaust rocker arm is locked in the actuation cavity when the reset check valve is in the closed position, and flows through the reset check valve when the reset check valve is in the open position. The slider-piston is associated with the reset check valve so that in an extended position of the slider-piston the reset check valve is free to move toward the closed position, and in a retracted position of the slider-piston the reset check valve is moved to the open position thereof by the slider-piston.

A compression-release engine brake system for effectuating a compression-release engine braking operation of an internal combustion engine. The compression-release system includes a lost motion exhaust rocker assembly including an exhaust rocker arm, an actuation device including an actuation piston and an actuation cavity, and a reset device including a reset check valve and a slider-piston. Hydraulic fluid in the exhaust rocker arm is locked in the actuation cavity when the reset check valve is in the closed position, and flows through the reset check valve when the reset check valve is in the open position. The slider-piston is associated with the reset check valve so that in an extended position of the slider-piston the reset check valve is free to move toward the closed position, and in a retracted position of the slider-piston the reset check valve is moved to the open position thereof by the slider-piston.

Methods and systems are provided for engine braking in a vehicle. In one example, a method may include deactivating fueling to at least one cylinder of an engine, increasing an air mass provided to the engine via an electric boosting device, and adjusting an exhaust valve opening timing of the at least one cylinder in response to a request for engine braking. In this way, an amount of engine braking torque may be increased with reduced wear to engine system components.

Methods and systems are provided for engine braking in a vehicle. In one example, a method may include deactivating fueling to at least one cylinder of an engine, increasing an air mass provided to the engine via an electric boosting device, and adjusting an exhaust valve opening timing of the at least one cylinder in response to a request for engine braking. In this way, an amount of engine braking torque may be increased with reduced wear to engine system components.

Methods and systems are provided for engine braking in a vehicle. In one example, a method may include deactivating fueling to at least one cylinder of an engine, increasing an air mass provided to the engine via an electric boosting device, and adjusting an exhaust valve opening timing of the at least one cylinder in response to a request for engine braking. In this way, an amount of engine braking torque may be increased with reduced wear to engine system components.