An exhaust passage structure of an internal combustion includes a first merging passage, a second merging passage, and a third merging passage connecting a third gathering portion in which the exhaust gas flowing through the first merging passage and the exhaust gas flowing through the second merging passage gather and a turbine of a turbocharger. The first merging passage and the second merging passage have respective narrowed portions in which passage cross-sectional areas are minimized. When a total value of passage cross-sectional areas of inlets of exhaust ports in one cylinder is set as a reference passage cross-sectional area A, and the passage cross-sectional areas of the narrowed portions of the first merging passage and the second merging passage are set as narrowed cross-sectional areas B, the exhaust passage structure is configured such that the relationship of 0.5≤(B/A)≤1 is established.

A turbine connector in an engine exhaust manifold includes a turbine foot attached to incoming exhaust conduits. The turbine foot has an outer perimetric edge defining a trapezoidal shape, and inner perimetric edges forming exhaust outlets from the incoming exhaust conduits. The inner perimetric edges have varied perimetric curvatures largest in finite curvature size upon a web extending between the exhaust outlets, and together forming an hourglass web profile in a turbine-mounting plane defined by the turbine foot.

An exhaust device for an internal combustion engine includes an exhaust manifold including branch pipe portions respectively connected to cylinders of the internal combustion engine in which exhaust strokes are executed at different timings, and a collecting pipe portion to which the branch pipe portions are collected and connected at a downstream side of the branch pipe portions, a catalyst provided at a downstream side of the collecting pipe portion in the exhaust manifold, an exhaust pipe provided at a downstream side of the catalyst, a sensor detecting a state of exhaust gas and provided in the exhaust pipe, and a connecting wall portion connecting the catalyst and the exhaust pipe and extending in a different direction with respect to a first central axis of the catalyst along a flow direction of the exhaust gas.

An exhaust manifold comprises a plurality of exhaust intake conduits structured to be fluidly coupled to an engine and receive exhaust gas from a corresponding cylinder of the engine. At least one exhaust intake conduit provides a reduction in an exhaust intake conduit cross-sectional area from an inlet to an outlet. A plurality of bends are each defined by a respective one of the exhaust intake conduit outlets. An exhaust intake manifold is fluidly coupled to the exhaust intake manifold and defines an exhaust intake manifold flow axis. Each of the plurality of bends is shaped so as to define n angle of approach of exhaust gas flowing therethrough. A first angle of approach of the first bend relative to the exhaust intake manifold flow axis is smaller than a second angle of approach of an inner second bend.

Methods and systems are provided for detection of cylinder misfire in an engine. In one example, a system may comprise a first cylinder and second cylinder of the engine having exhaust flows combined together in an exhaust system before being combined with other cylinders of the engine. The first cylinder and second cylinder may share an exhaust gas sensor mounted in the exhaust in a position to sense exhaust from the first cylinder and second cylinder, and being positioned before exhaust from other cylinders is combined with sensed exhaust from the first cylinder and second cylinder. The system may further include a control system with instructions stored therein to indicate detected misfire in one or more of the first and second sensors based on an output from the exhaust gas sensor.

An applied-ignition internal combustion engine includes first and second combustion chambers, an exhaust-gas system with an exhaust-gas purification system is disposed at the first and second combustion chambers, and an exhaust-gas manifold. An exhaust gas from a combustion of a fuel/air mixture firstly flows through the exhaust-gas manifold and subsequently flows through the exhaust-gas purification system. A first section of the exhaust-gas system from the first combustion chamber to the exhaust-gas purification system is cooled more than a second section of the exhaust-gas system from the second combustion chamber to the exhaust-gas purification system. The first combustion chamber is operated with a lean fuel/air mixture, the second combustion chamber is operated with a rich fuel/air mixture, and an overall exhaust-gas lambda value at an inlet into the exhaust-gas purification system is stoichiometric.

The invention relates to an internal combustion engine system (100), comprising: —an internal combustion engine (2) comprising a cylinder block (3) housing a plurality of cylinders (4), a first intake manifold (6a) connected to a first group of cylinders (4a) a second distinct intake manifold (6b) connected to a second group of cylinders (4b) and a first, respectively a second, exhaust manifold (8a, 8b) for receiving the exhaust gas emitted from the first, respectively the second, group of cylinders (4a, 4b); —an air inlet line (10); —an EGR line (20) connected to the first and second exhaust manifolds (8a, 8b); wherein the internal combustion engine system is operable in at least two operating modes, respectively a normal operating mode in which all cylinders are supplied with fuel and a regeneration operating mode, in which the cylinders of the first group of cylinders (4a) are no longer supplied with fuel, characterized in that: —the system also includes a mixing unit (30) comprising a four-way valve, said four-way valve (30) having a first inlet (31) connected to the EGR line (20), a second inlet (32) connected to the air inlet line (10), a first outlet (33) connected to the first intake manifold (6a) and a second outlet (34) connected to the second intake manifold (6b); —the four-way valve is designed so that, in said normal operating mode, the intake gases supplied to the first intake manifold (6a) and to the second intake manifold (6b) have approximately the same proportion of exhaust gas and so that, in said regeneration operating mode, the intake gas supplied to the first intake manifold (6a) only includes exhaust gas.

An exhaust manifold for an internal combustion engine is provided. The manifold comprises at least one first exhaust gas inlet connectable to a first bank of cylinders of the engine, and at least one second exhaust gas inlet connectable to a second bank of cylinders of the engine. First and second exhaust gas outlets are connectable to respective first and second volutes of a twin volute turbocharger. At least one wastegate outlet is connectable to a bypass passage which bypasses the turbocharger. A diverter valve is located within the manifold, wherein the diverter valve is adapted to selectively direct exhaust gas from the first and second inlets to at least one of the first and second exhaust gas outlets and the wastegate outlet. A turbocharger is also provided having the same diverter valve arrangement, as are internal combustion engines having either the manifold or turbocharger, and a vehicle having such an internal combustion engine.

Methods and systems are provided for increasing engine power via partial engine enrichment and exhaust gas recirculation. In one example, a method may include enriching a first set of engine cylinders, enleaning a second set of the engine cylinders, and operating a third set of the engine cylinders at stoichiometry, exhaust gas from all of the engine cylinders producing a stoichiometric mixture at a downstream emission control device, and providing exhaust gas recirculation (EGR) to an intake passage of the engine from the first set of cylinders. In this way, cooling effects from the partial enrichment and the EGR enable engine air flow, and thus engine power, to be increased while an efficiency of the emission control device is maintained, thereby decreasing vehicle emissions.

An exhaust pulse balance chamber comprising a circular collar, mid-section that bulges at its center, skirt, and right and left legs, all of which are sealed to the exterior environment and in fluid communication with one another. The outer diameter of the skirt increases in width but not in depth from the proximal end of the skirt to the distal end of the skirt, which is configured to receive the right and left legs. Each leg is bent at a 30-degree angle relative to the central longitudinal axis of the exhaust pulse balance chamber. The invention includes a method of using the exhaust pulse balance chamber to convert a vehicle from a dual-in, single-out exhaust system to a dual-in, dual-out exhaust system.