A method for operating an engine is disclosed. The method may include supplying air from a primary air supply unit to an intake conduit. The method may also include supplying air to the engine from the intake conduit. The method may further include selectively supplying air from a secondary air supply unit to the intake conduit. In addition, the method may include maintaining an air fuel ratio between a first threshold value and a second threshold value during an increase in engine load increase by controlling a supply of air from the secondary supply unit to the intake conduit.

The objective is to improve driving feeling at a time of acceleration operation or deceleration operation, by recognizing driver's intention of acceleration or deceleration during straight-ahead running. A driving-assistance control apparatus according to the present disclosure includes a straight-running determination unit that determines whether or not a vehicle is running straight, a head-position detection unit that detects a head position of a driver, a driving-posture determination unit that determines the posture of the driver, based on the head position detected by the head-position detection unit, and a driving-assistance control unit that performs acceleration preparation control for raising a reaction speed for acceleration operation or deceleration preparation control for raising a reaction speed for deceleration operation in accordance with an output of the driving-posture determination unit, when the straight-running determination unit determines that a vehicle is running straight.

The objective is to improve driving feeling at a time of acceleration operation or deceleration operation, by recognizing driver's intention of acceleration or deceleration during straight-ahead running. A driving-assistance control apparatus according to the present disclosure includes a straight-running determination unit that determines whether or not a vehicle is running straight, a head-position detection unit that detects a head position of a driver, a driving-posture determination unit that determines the posture of the driver, based on the head position detected by the head-position detection unit, and a driving-assistance control unit that performs acceleration preparation control for raising a reaction speed for acceleration operation or deceleration preparation control for raising a reaction speed for deceleration operation in accordance with an output of the driving-posture determination unit, when the straight-running determination unit determines that a vehicle is running straight.

An engine sound enhancement system includes a conduit in communication with at least one of an intake manifold and an exhaust manifold of an engine. An interface is arranged at least one of within the conduit and between an inlet of the conduit and the at least one of the intake manifold and the exhaust manifold. The interface is responsive to pulses within the at least one of the intake manifold and the exhaust manifold, wherein the interface is configured to transfer the pulses into the conduit.

An engine sound enhancement system includes a conduit in communication with at least one of an intake manifold and an exhaust manifold of an engine. An interface is arranged at least one of within the conduit and between an inlet of the conduit and the at least one of the intake manifold and the exhaust manifold. The interface is responsive to pulses within the at least one of the intake manifold and the exhaust manifold, wherein the interface is configured to transfer the pulses into the conduit.

A method and apparatus is disclosed to control the operation of an air charging system of an internal combustion engine. A plurality of output parameters of the air charging system are monitored. An error is calculated between the monitored output parameters and a target value thereof. The calculated errors are applied to a linear controller that yields a virtual input used to calculate a plurality of input parameters for the air charging system. The input parameters is used to determine the position of a corresponding actuator of the air charging system for operating the actuators according to the determined position thereof. The inputs parameters are calculated with a non-linear mathematical model of the air charging system configured such that the virtual inputs are in a linear relation with only one of the output parameters and vice versa.

A four-cycle internal combustion engine has a permanent curtailed intake process, which allows the temperature and pressure of intake air to the combustion cylinders to be tightly controlled, and enables a very small combustion chamber so that a much higher compression ratio and pre-ignition compression pressure can be achieved without approaching the air/fuel mixture auto-ignition threshold. The maximum threshold of curtailed intake volume is determined to be 68% of engine cylinder volume to achieve a compression ratio CR of 22.1 or higher. Because this design can effectively regulate and set the maximum pre-ignition temperature of the fuel-air mixture, it can combust virtually any type of liquid hydrocarbon fuel without knocking. This four-cycle engine, due to its higher compression ratio, generates power equivalent to or greater than a standard four-cycle engine in a smaller and lighter engine and at a much higher efficiency.

A four-cycle internal combustion engine has a permanent curtailed intake process, which allows the temperature and pressure of intake air to the combustion cylinders to be tightly controlled, and enables a very small combustion chamber so that a much higher compression ratio and pre-ignition compression pressure can be achieved without approaching the air/fuel mixture auto-ignition threshold. The maximum threshold of curtailed intake volume is determined to be 68% of engine cylinder volume to achieve a compression ratio CR of 22.1 or higher. Because this design can effectively regulate and set the maximum pre-ignition temperature of the fuel-air mixture, it can combust virtually any type of liquid hydrocarbon fuel without knocking. This four-cycle engine, due to its higher compression ratio, generates power equivalent to or greater than a standard four-cycle engine in a smaller and lighter engine and at a much higher efficiency.

A method of operating an engine includes determining an intake air temperature and an engine speed. The method includes selectively initiating one of a first operating mode, a second operating mode and a third operating mode based on at least the intake air temperature and the engine speed. The first operating mode includes increasing the engine speed progressively by an incremental speed value. The second operating mode includes deactivating at least one Exhaust Gas Recirculation (EGR) cylinder of the engine. The third operating mode includes shutting down the engine.

A method of operating an engine includes determining an intake air temperature and an engine speed. The method includes selectively initiating one of a first operating mode, a second operating mode and a third operating mode based on at least the intake air temperature and the engine speed. The first operating mode includes increasing the engine speed progressively by an incremental speed value. The second operating mode includes deactivating at least one Exhaust Gas Recirculation (EGR) cylinder of the engine. The third operating mode includes shutting down the engine.