Abstract: An air intake system for an internal combustion engine includes a manifold defining a chamber in which air is distributed to a plurality of engine cylinders. The chamber includes an inlet and a plurality of outlets, each outlet providing fluid communication between the chamber and an engine cylinder. Each of the plurality of outlets is substantially the same distance from the inlet to provide more consistent gas flow rates through the outlets. The air intake system preferably includes a plurality of runners. Each of the plurality of runners defines a passageway that interconnects one of the outlets to a respective engine cylinder. Each passageway is characterized by the same length and the same cross sectional area.

Abstract: An air intake system for an internal combustion engine includes a manifold defining a chamber. The chamber is divided into a first chamber portion and a second chamber portion by a permeable member for fluid communication between the first chamber portion and the second chamber portion. The permeable member facilitates mixing of air and exhaust gas for more consistent EGR distribution among a plurality of cylinders.

Abstract: An air intake system for an internal combustion engine includes a conduit defining a passageway that conveys air to a manifold. An EGR inlet in the conduit enables EGR to mix with the air. A plate is sufficiently positioned in the passageway such that air in the passageway is divided into two streams. One of the streams flows on one side of the plate and the other stream flows on the other side of the plate. The plate is sufficiently positioned with respect to the EGR inlet such that at least some of the EGR, and preferably the greater part of the EGR entering the passageway, is diverted to flow on only one side of the plate. The plate deflects at least some of the EGR such that it has more time and space in which to mix with the air before being ingested in an engine cylinder. The plate thus enables more consistent EGR distribution among engine cylinders, resulting in better emissions and fuel economy compared to the prior art.

Abstract: Superior piston bowl and combustion chamber configurations are designed for a reverse tumble spark ignition direct injection engine. The piston includes a shallow bowl extending from adjacent an edge of the piston head to an inner side slightly beyond a peak. The bowl features a bowl lip re-entrant angle at the spark plug location having an open or positive re-entrant angle. On lateral edges of the bowl between the inner and outer edges, wing like extensions include negative re-entrant angles. These help contain the injected fuel within the bowl during combustion. Other features of the combustion chamber include vertical intake ports that produce a weak reverse tumbling air flow motion with a tumble ratio of about 0.6, which allows increased flow efficiency of the port. An injector spray cone angle of 90 degrees is preferred with a bowl sized to capture the spray. Various additional features are disclosed.

Abstract: Superior piston bowl and combustion chamber configurations are designed for a reverse tumble spark ignition direct injection engine. The piston includes a shallow bowl extending from adjacent an edge of the piston head to an inner side slightly beyond a peak. The bowl features a bowl lip re-entrant angle at the spark plug location having an open or positive re-entrant angle. On lateral edges of the bowl between the inner and outer edges, wing like extensions include negative re-entrant angles. These help contain the injected fuel within the bowl during combustion. Other features of the combustion chamber include vertical intake ports that produce a weak reverse tumbling air flow motion with a tumble ratio of about 0.6, which allows increased flow efficiency of the port. An injector spray cone angle of 90 degrees is preferred with a bowl sized to capture the spray. Various additional features are disclosed.