A method for controlling vehicle speed comprises selecting an engine speed profile for a vehicle. Road grade data is received and processed to determine a road grade for the vehicle. Vehicle speed data is received and processed to determine a vehicle speed for the vehicle. A cylinder deactivation mode for a valvetrain of a multi-cylinder engine of the vehicle is selected. The cylinder deactivation mode comprises deactivating one or more intake valve, exhaust valve, and fuel injection for one or more cylinder of the multi-cylinder engine. The selected cylinder deactivation mode provides a controlled deviation from the selected engine speed profile at the road grade and vehicle speed.

A continuously variable valve duration (CVVD) system includes an electronic control unit (ECU) configured to output a command for adjusting an actuator and a controller configured to determine a operation range of a control shaft of the actuator and adjust the control shaft in the determined operation range based on the command of the ECU. The controller positions the control shaft at a predetermined target phase and determines a control state of each target phase based on a target phase value transmitted from the actuator when the control shaft is positioned at the target phase.

Intake holes at the opposite ends are opened and closed by first intake valves. The middle intake hole is opened and closed by a second intake valve. A control device includes an intake variable valve device. First branch channels are connected to the intake holes and produce a normal tumble flow. A second branch channel is configured such that the flow rate of intake air passing through the middle intake hole is relatively greater on the side closer to the outer periphery of the combustion chamber. Where increasing the flow coefficient is given a higher priority, a three-valve drive mode is selected. Where the strength of the normal tumble flow is enhanced, a two-valve drive mode is selected. Where production of the normal tumble flow is reduced, a one-valve drive mode is selected.

An internal combustion engine includes an electro-hydraulic system for variable actuation of intake valves where each cylinder has two intake valves, associated with two intake conduits. A first conduit is generates within the cylinder a tumble motion of airflow introduced therein, when the intake valve associated thereto is at least partially opened. The second intake conduit generates within the cylinder a swirl motion of airflow introduced therein when the second intake valve is at least partially opened. A controller of controls one or more control valves to open only one of the intake valves of each cylinder in a condition of reduced engine operation, below a predetermined load and/or a predetermined speed of the engine, and to always open both intake valves in the remaining conditions of engine operation. The first intake valve is the only valve to be opened in the reduced engine operation condition.

A method for advancing valve actuation during low load or idle diesel engine conditions to promote aftertreatment heat up comprises switching a cam phaser from a nominal lift position to an advance lift position to open an affiliated valve before nominal. Valve lift is actuated via the cam phaser. The valve is lowered towards nominal closure, and valve closure is interrupted by actuating a latch phaser. Valve closure is extended beyond nominal valve closure.

Systems and methods for managing excessive intake flow path pressure and counter flow are implemented to support enhanced engine braking applications, such as 2-stroke or 1.5-stroke engine braking implementations where the intake flow path may be exposed to excessive transient pressures in the combustion chamber during activation or deactivation of an engine brake. Intake throttle, exhaust gas recirculation (EGR) valve, intake manifold blow-off valve, compressor bypass valve, exhaust throttle, turbocharger geometry or turbocharger waste gate may be controlled to effectuate counter flow management separately or in combination. Excessive transient conditions may also be prevented or managed by sequential valve motion in which brake motion activation occurs first and then exhaust valve main event deactivation occurs second. Delay between brake activation and main event deactivation may be facilitated using mechanical and/or hydraulic implements as well as electronically.

A rocker arm assembly operable in an engine drive mode and at least one of a late intake valve closing (LIVC) mode and an internal exhaust gas recirculation (iEGR) mode, the rocker arm assembly selectively opening first and second engine valves. The rocker arm assembly includes a rocker arm configured to rotate about a rocker shaft, and a reverse reset capsule assembly movable between (i) a locked position configured to perform one of an LIVC operation and an iEGR operation, and (ii) an unlocked position that does not perform the LIVC operation or the iEGR operation. An actuator assembly is configured to selectively move the reverse reset capsule assembly between the locked and unlocked positions.

An internal combustion engine system includes an engine with a plurality of pistons housed in respective ones of a plurality of cylinders, an air intake system to provide air to the plurality of cylinders through respective ones of a plurality of intake valves, an exhaust system to release exhaust gas from the plurality of cylinders through respective one of a plurality of exhaust valves. A valve train is provided for cylinder deactivation of a first part of the plurality of cylinders and compression release braking on a second part of the plurality of cylinders.

Closing timing of an intake port is changed without using a variable valve timing mechanism. An electric vehicle includes an engine for electricity generation in which closing timing of an intake port maximizes intake air charging efficiency in a specific revolution speed region, a sensor which outputs a signal related to a revolution speed of the engine, a controller which drives the engine at a revolution speed based on the signal of the sensor, a requested electricity generation amount being satisfied at the revolution speed, and a motor which applies a positive or negative torque to the engine. When the engine is driven in a revolution speed region other than the specific revolution speed region, the controller uses the motor to apply a positive or a negative torque to the engine in an intake stroke to change the closing timing of the intake port to increase intake air charging efficiency.

Systems and methods to extend a life of a component of a cylinder deactivation system are provided. A method includes generating, by a controller, an initial life factor for the component; initiating, by the controller, a CDA mode for an engine; determining, by the controller, an actual life factor for the component, the actual life factor determined by comparing a number of switching events of a cylinder in the CDA mode to a number of cycles of the cylinder in the CDA mode; comparing, by the controller, the actual life factor to the initial life factor; and modifying, by the controller based on the comparison, operation of the engine in the CDA mode to adjust the actual life factor.