An exhaust gas recirculation (EGR) passage is connected with an intake passage (a bypass passage bypassing a supercharger) of an engine. The EGR passage includes, in a position close to a connection port to the intake passage, an expanding portion in which a passage cross-sectional area expands and which lowers a flow speed of EGR gas so as to reduce an uneven flow, in the connection port, of the EGR gas flowing into the intake passage.

An exhaust gas recirculation (EGR) passage is connected with an intake passage (a bypass passage bypassing a supercharger) of an engine. The EGR passage includes, in a position close to a connection port to the intake passage, an expanding portion in which a passage cross-sectional area expands and which lowers a flow speed of EGR gas so as to reduce an uneven flow, in the connection port, of the EGR gas flowing into the intake passage.

A spark ignited internal combustion engine is controlled in response to a self-learned TOB reference. The self-learned TOB reference is based on a difference between a learned TOB offset and a desired or target TOB, and a sensed TOB. The learned TOB offset at a given operating condition, such as charge pressure, can be found by interpolating between the learned charge pressure breakpoints in a TOB learning algorithm. The TOB learning algorithm can include using a filtered charge pressure value to indicate the engine load at which the TOB is learned. An index determination is made with a look up table with charge pressure as an input and an array index of learned charge pressure and learned TOB offset as outputs.

Disclosed is a fluid damping system for a planetary traction drive designed for a driven turbocharger on an engine. The planetary traction drive has a plurality of double roller planets that are each supported by two planet hearings, one at each end of the double roller planet. Each planet bearing has a fluid damping system that consists of a radial squeeze film damper that feeds fluid to an axial squeeze film damper to absorb vibrations and dissipate kinetic energy in the planetary traction drive.

Disclosed is a fluid damping system for a planetary traction drive designed for a driven turbocharger on an engine. The planetary traction drive has a plurality of double roller planets that are each supported by two planet hearings, one at each end of the double roller planet. Each planet bearing has a fluid damping system that consists of a radial squeeze film damper that feeds fluid to an axial squeeze film damper to absorb vibrations and dissipate kinetic energy in the planetary traction drive.

Methods and systems are provided for split exhaust engine system including a blowdown exhaust manifold coupled to an exhaust passage and a scavenge exhaust manifold coupled to an intake passage. In one example, a turbine wastegate couples a single exhaust runner out of a plurality of exhaust runners of the blowdown exhaust manifold to an exhaust passage, downstream of a turbocharger turbine. Additionally, the turbine wastegate may couple the single exhaust runner to the exhaust passage, downstream of the turbocharger turbine arranged in the exhaust passage.

Methods and systems are provided for split exhaust engine system including a blowdown exhaust manifold coupled to an exhaust passage and a scavenge exhaust manifold coupled to an intake passage. In one example, a turbine wastegate couples a single exhaust runner out of a plurality of exhaust runners of the blowdown exhaust manifold to an exhaust passage, downstream of a turbocharger turbine. Additionally, the turbine wastegate may couple the single exhaust runner to the exhaust passage, downstream of the turbocharger turbine arranged in the exhaust passage.

An exhaust gas recirculation (EGR) passage is connected with an intake passage (a bypass passage bypassing a supercharger) of an engine. The EGR passage includes, in a position close to a connection port to the intake passage, an expanding portion in which a passage cross-sectional area expands and which lowers a flow speed of EGR gas so as to reduce an uneven flow, in the connection port, of the EGR gas flowing into the intake passage.

A method for reducing NOx emissions during operation of an internal combustion engine in commerce which, when burning hydrocarbon fuel as a primary fuel, in the absence of any secondary fuel, has a characteristic stoichiometric ration. The method includes the following: in the absence of electrolytic activity, providing and entraining a quenching species in a gaseous medium and then interacting the quenching species with constituents present during oxidation of the primary fuel in a combustion chamber of the engine.

A method for reducing NOx emissions during operation of an internal combustion engine in commerce which, when burning hydrocarbon fuel as a primary fuel, in the absence of any secondary fuel, has a characteristic stoichiometric ration. The method includes the following: in the absence of electrolytic activity, providing and entraining a quenching species in a gaseous medium and then interacting the quenching species with constituents present during oxidation of the primary fuel in a combustion chamber of the engine.