Abstract: An internal combustion engine defines a plurality of cylinders including full-time active cylinders and cylinders capable of being deactivated. A turbocharger having a twin scroll turbine includes a first turbine scroll in communication with the exhaust passages from the full-time active cylinders and a second turbine scroll in communication with the exhaust passages from the cylinders capable of being deactivated. A scroll control valve is provided in communication with the exhaust passages from the cylinders capable of being deactivated and being operable in an open position to allow exhaust gases from the cylinders capable of being deactivated to pass through the second turbine scroll, and being operable in a closed position to direct exhaust gases from the plurality of second cylinders capable of being deactivated to pass through the first turbine scroll.

Abstract: According to one embodiment of the invention, a secondary air injection system includes a first conduit in fluid communication with at least one first exhaust passage of the internal combustion engine and a second conduit in fluid communication with at least one second exhaust passage of the internal combustion engine, wherein the at least one first and second exhaust passages are in fluid communication with a turbocharger. The system also includes an air supply in fluid communication with the first and second conduits and a flow control device that controls fluid communication between the air supply and the first conduit and the second conduit and thereby controls fluid communication to the first and second exhaust passages of the internal combustion engine.

Abstract: In one exemplary embodiment of the invention, a housing for an internal combustion engine includes a manifold section configured to receive an exhaust gas flow from cylinders of the internal combustion engine and a turbine section, wherein the turbine section and manifold section are a single member. Further, the housing includes a volute chamber within the turbine section configured to direct the exhaust gas flow to a turbine wheel disposed about a turbine axis and a circumferential septum positioned inside the volute chamber to separate two chambers that are substantially nested about the turbine wheel.

Abstract: According to one embodiment of the invention, a secondary air injection system includes a first conduit in fluid communication with at least one first exhaust passage of the internal combustion engine and a second conduit in fluid communication with at least one second exhaust passage of the internal combustion engine, wherein the at least one first and second exhaust passages are in fluid communication with a turbocharger. The system also includes an air supply in fluid communication with the first and second conduits and a flow control device that controls fluid communication between the air supply and the first conduit and the second conduit and thereby controls fluid communication to the first and second exhaust passages of the internal combustion engine.