An air intake apparatus includes a plurality of funnel-shaped portions provided in a plurality of intake ports. The plurality of funnel-shaped portions respectively include open ends located at positions at which lengths of the plurality of intake ports are aligned with each other, the open ends being provided along a direction perpendicular to a direction in which respective centerlines of the plurality of intake ports extend.

An air intake apparatus includes a plurality of funnel-shaped portions provided in a plurality of intake ports. The plurality of funnel-shaped portions respectively include open ends located at positions at which lengths of the plurality of intake ports are aligned with each other, the open ends being provided along a direction perpendicular to a direction in which respective centerlines of the plurality of intake ports extend.

A system for manufacturing a family of intake manifolds includes first and second intake molds. One of the first and second intake molds includes an outlet insert. A first intake manifold includes: a plenum chamber, a plenum chamber air inlet; a first number of intake runner passages; and the first number of outlets. Each of the outlets is fluidly connected to a corresponding one of the first number of intake runner passages. The second intake manifold includes: the plenum chamber; the plenum chamber air inlet; the first number of intake runner passages; and a second number of outlets. Each of the second number of outlets is fluidly connected to a corresponding one of the first number of intake runner passages. At least one of the first number of intake runner passages is not fluidly connected to any one of the second number of outlets of the second intake manifold.

A system for manufacturing a family of intake manifolds includes first and second intake molds. One of the first and second intake molds includes an outlet insert. A first intake manifold includes: a plenum chamber, a plenum chamber air inlet; a first number of intake runner passages; and the first number of outlets. Each of the outlets is fluidly connected to a corresponding one of the first number of intake runner passages. The second intake manifold includes: the plenum chamber; the plenum chamber air inlet; the first number of intake runner passages; and a second number of outlets. Each of the second number of outlets is fluidly connected to a corresponding one of the first number of intake runner passages. At least one of the first number of intake runner passages is not fluidly connected to any one of the second number of outlets of the second intake manifold.

An intake swirl gasket is disclosed herein. It is installed between a cylinder head and an intake manifold and comprises plural airflow holes for respectively communicating with plural intake passages of the cylinder head; and plural diversion devices respectively disposed in the plural airflow holes and each having an axis and plural splitter blades extended from the axis for connecting to an inner wall of each of the plural airflow holes, wherein each of the plural splitter blades is shaped as an arc to form a recessed surface towards the intake manifold at one side thereof and a convex surface towards the cylinder head at the other side thereof, and wherein an included angle between each of the plural splitter blades and an end face of the intake swirl gasket oriented towards the cylinder head ranges from 50 to 80 degrees.

An intake swirl gasket is disclosed herein. It is installed between a cylinder head and an intake manifold and comprises plural airflow holes for respectively communicating with plural intake passages of the cylinder head; and plural diversion devices respectively disposed in the plural airflow holes and each having an axis and plural splitter blades extended from the axis for connecting to an inner wall of each of the plural airflow holes, wherein each of the plural splitter blades is shaped as an arc to form a recessed surface towards the intake manifold at one side thereof and a convex surface towards the cylinder head at the other side thereof, and wherein an included angle between each of the plural splitter blades and an end face of the intake swirl gasket oriented towards the cylinder head ranges from 50 to 80 degrees.

A combustion control device for an engine includes a plurality of cylinders, a surge tank disposed in an intake path to the cylinders, an independent intake passage connecting the surge tank and an intake port of each of the cylinders, a fuel injection valve that is disposed for each of the cylinders and that supplies fuel into each of the cylinders, and a control unit that controls a fuel injection amount of each of the fuel injection valves according to an engine operating state. The control unit corrects a target fuel injection amount of each of the cylinders, the target fuel injection amount being determined according to the engine operating state, based on a re-intake correction amount set in each of the cylinders according to a re-intake amount of intake air from the intake port in internal EGR in each of the cylinders.

An intake manifold includes a passage wall portion having a first member passage wall portion provided at a first member, a second member passage wall portion provided at a second member, and an inner joint portion including a division point at which an inner joint portion is divided from an outer peripheral joint portion, the inner joint portion at which the first member passage wall portion and the second member passage wall portion are joined with each other. At least a part of the inner joint portion except for the division point is arranged at a height position closer to a middle part of a gas passage than the division point in a first direction in which the first member and the second member are opposed with each other.

An intake manifold includes a passage wall portion having a first member passage wall portion provided at a first member, a second member passage wall portion provided at a second member, and an inner joint portion including a division point at which an inner joint portion is divided from an outer peripheral joint portion, the inner joint portion at which the first member passage wall portion and the second member passage wall portion are joined with each other. At least a part of the inner joint portion except for the division point is arranged at a height position closer to a middle part of a gas passage than the division point in a first direction in which the first member and the second member are opposed with each other.

An engine system may include: an engine including cylinders that generate a driving torque by combusting fuel; a first intake manifold connected to an intake line through which flows intake air into some of the plurality of cylinders; a second intake manifold supplying the intake air to the other cylinders of the plurality of cylinders through the first intake manifold; a first exhaust manifold connected to some cylinders that are connected to the first intake manifold; a second exhaust manifold connected to some other cylinders that are connected to the second intake manifold; a recirculation line branched from the second exhaust manifold to be coupled to the second intake manifold; a recirculation inlet valve disposed at a point at which the recirculation line and the second exhaust manifold are joined; and a manifold connection valve disposed on an intake line between the first intake manifold and the second intake manifold.