Various methods and systems are provided for a multi-fuel capable engine. In one example, a system comprises an engine having at least one cylinder controlled via an intake valve, a first fuel system to deliver liquid fuel and a second fuel system to deliver gaseous fuel to the at least one cylinder, a variable valve timing actuation system to adjust one or more of an opening or a closing timing of the intake valve, and a controller. The controller is configured to, during a liquid fuel only mode, adjust the variable valve timing actuation system to close the intake valve at a first timing based at least on engine load, and during a multi-fuel mode, adjust the variable valve timing actuation system to close the intake valve at a second timing.

An internal combustion engine is provided. Facing pistons eliminate a cylinder head, thereby reducing heat losses through a cylinder head. Facing pistons also halve the stroke that would be required for one piston to provide the same compression ratio, and the engine can thus be run at higher revolutions per minute and produce more power. An internal sleeve valve is provided for space and other considerations. A combustion chamber size-varying mechanism allows for adjustment of the minimum size of an internal volume to increase efficiency at partial-power operation. Variable intake valve operation is used to control engine power.

An internal combustion engine includes an intake variable lift amount mechanism that changes a maximum lift amount and valve-open period of an intake valve, and an exhaust variable lift amount mechanism that changes a maximum lift amount and valve-open period of an exhaust valve. A control unit executes a process to increase the valve-open period of the intake valve and reduce the valve-open period of the exhaust valve, when idling with a temperature of the internal combustion engine that is equal to or higher than a reference value.

A method of providing a rocker arm set for a valvetrain includes providing a first intake rocker arm, a second intake rocker arm and a first exhaust rocker arm. The first intake rocker arm is configured as a switching rocker arm for a first intake valve on a first cylinder. The second intake rocker arm is for a second intake valve on a second cylinder. The second rocker arm is configured to operate in a normal Otto cycle mode. The first exhaust rocker arm is provided for a first exhaust valve on the second cylinder. The first intake rocker arm operates in one of an LIVC or EIVC mode where the first intake rocker arm is configured to open or close at a different time compared to the second intake valve. The first exhaust rocker arm operates in a cylinder deactivation mode.

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 reciprocating, internal combustion engine comprises a turbine connected to the exhaust port of a cylinder. The turbine receives exhaust gas from the cylinder and a power capture means transfers the power generated by the turbine to at least one of power storage device, a turbocharger, a compressor, and vehicle locomotion.

A method of providing a rocker arm set for a valvetrain includes providing a first intake rocker arm, a second intake rocker arm and a first exhaust rocker arm. The first intake rocker arm is configured as a switching rocker arm for a first intake valve on a first cylinder. The second intake rocker arm is for a second intake valve on a second cylinder. The second rocker arm is configured to operate in a normal Otto cycle mode. The first exhaust rocker arm is provided for a first exhaust valve on the second cylinder. The first intake rocker arm operates in one of an LIVC or EIVC mode where the first intake rocker arm is configured to open or close at a different time compared to the second intake valve. The first exhaust rocker arm operates in a cylinder deactivation mode.

In certain embodiments, Lube Oil Controlled Ignition (LOCI) Engine Combustion overcomes the drawbacks of known combustion technologies. First, lubricating oil is already part of any combustion engine; hence, there is no need to carry a secondary fuel and to have to depend on an additional fuel system as in the case of dual-fuel technologies. Second, the ignition and the start of combustion rely on the controlled autoignition of the lubricating oil preventing the occurrence of abnormal combustion as experienced with the Spark Ignition technology. Third, LOCI combustion is characterized by the traveling of a premixed flame; hence, it has a controllable duration resulting in a wide engine load-speed window unlike the Homogeneous Charge Compression Ignition technology where the engine load-speed window is narrow. Adaptive Intake Valve Closure may be used to control in-cylinder compression temperature to be high enough to realize the consistent auto ignition of the lubricating oil mist.

Systems, apparatus, and methods are disclosed that include an internal combustion engine having a plurality of cylinders and controlling the intake manifold pressure during early intake valve opening to reduce or prevent oil consumption.

A variable valve timing assembly is provided for extending a duration of an intake valve opening. The variable valve timing assembly includes an intake rocker mounted on a pedestal and operable by a cam lobe to open and close the intake valve. The intake rocker includes a lever extension, and a holding member in the pedestal is lockable in position by a hydraulic circuit in the pedestal to contact the lever extension of the intake rocker and hold the intake valve in the open position. A reset pin in the pedestal is actuatable by the cam lobe to release the holding member to allow the intake valve to close.