To provide an intake manifold which can reliably prevent the step from being formed in the inner wall surface of the intake passage (15) while having provided therein the fitting holding portion (32) for fitting and holding the flame arrester (25) in the axial direction, the intake manifold (10) includes a base member (21), a cover member (22) and a flame arrester (25) having a flame suppression structure. Between the flame arrester (25) and the radical stepped surface (31b) of the recessed body portion (31) is provided a retaining rectifying member (23) that prevents the flame arrester (25) from coming off with respect to the fitting holding portion (32) and forms a third inner peripheral surface (23a) continuous without a step from an opening portion on the other end side (25b) of the flame arrester (25) to the base side second inner wall surface (31c).

There is provided an internal combustion engine in which respective combustion states of cylinders can be uniformized with a simple configuration. A central axis (CL1) of a connecting part (7) of one of air supply ports (5) inclines with a predetermined inclination angle in a direction away from an air supply inlet (3) with respect to a y direction orthogonal to an x direction in which an air supply manifold 1 extends, and an inclination angle of the connecting part (7) of the one of the air supply ports (5) is larger than an inclination angle of the connecting part (7) of other air supply ports (5) located on a side closer to the air supply inlet (3) than the one of the air supply ports (5).

A car intercooler pipe includes an inlet of the intercooler pipe positioned at an upper side of the car intercooler pipe, an upper corrugated portion having upper corrugated bodies protruding in a rib shape from a surface of a pipe body extending in a direction toward the inlet, an outlet of the intercooler pipe positioned at a lower side of the car intercooler pipe, a lower corrugated portion, and an intermediate portion bent downward from the upper corrugated portion and having the pipe body connected to the lower corrugated portion, wherein a thickness of the pipe body of the intermediate portion is greater than a thickness of the upper corrugated body of the upper corrugated portion and a thickness of the lower corrugated body of the lower corrugated portion, and wherein disconnection portions having corrugations with different heights are formed in the upper corrugated body and the lower corrugated body.

An engine component includes an intake manifold of stratified layers defining a plurality of runners each having a gas outlet leading to a cylinder head, and a plenum including partial walls that form channels radiating from a common gas inlet and transitioning into the runners such that there is no seal between the plenum and runners. The partial walls form endoskeletal structure configured to support the intake manifold.

An air-intake device comprises a vehicle body frame including a head box; and a pair of right and left main frames, wherein the head box includes: a casing section which extends between a front opening and a rear opening of the head box and is formed with a main air passage; and a pair of right and left extending sections coupled to the pair of main frames, respectively, wherein at least one extending section is provided with a branch air passage which branches from the main air passage, and wherein a separating wall is provided between the main air passage and the branch air passage and has a communication hole, and wherein when a vehicle body is viewed from a side, at least one extending section is extended rearward to a location at which at least a front region of the communication hole is covered by the extending section.

An intake system is for a marine drive. The intake system comprises a throttle device that receives intake air for combustion; an intake conduit that conveys the intake air to the throttle device, wherein the intake conduit has an upstream inlet end, a downstream outlet end, and a radially outer surface that extends from the upstream inlet end to the downstream outlet end; and an intake silencer coupled to the radially outer surface and configured to attenuate sound emanating from the intake system.

An intake passage structure for an engine includes an intake port in a cylinder head of the engine, and connected to a combustion chamber to define an intake passage. The intake passage structure further includes a heat insulating member disposed along an inner surface of the intake port, and including a bulge having an upstream end surface which is a portion of an upstream end surface of the heat insulating member, the bulge has a radially outwardly protruding radially outer surface and has an increased wall thickness. The wall thickness of the bulge increases from downstream to upstream of the intake port. The upstream end surface of the bulge includes an injection machine connecting portion facing an injection gate configured to inject resin for forming the heat insulating member into the intake port.

A positive crankcase ventilation system for an internal combustion engine routes blowby gases into the intake of the engine. Because the blowby gases have about 12% water vapor, during cold-weather operation, the water vapor may freeze in the PCV valve or in the port that couples the PCV duct with the intake manifold. In situations in which the PCV duct is pointing toward the direction of flow of the intake gases, a hood or cap is placed over the end of the tube according to the present disclosure. It can be as simple as a 90-degree elbow or multiple openings in the cap. A centerline of the openings is perpendicular or at an obtuse angle with respect to the direction of flow in the duct so that the intake gases do not directly access the openings and cause freezing in the openings (or ports).

Aspects of the present disclosure include branching fluid passages in an apparatus that reduce turbulent flow and generate evenly distributed fluid pressure as the fluids branch off into the different passages. In some embodiments, the branching passages may be subdivided into two sets: the branching passages for the liquid fuel and the branching passages for the liquid oxidizer. In some embodiments, the two sets of passages are carefully designed in an elegant yet extremely intricate manner that is optimized for proper fluid flow and maximal burn efficiency. The ends of all of the passages meet at the injector interface, which dispense the liquids into the combustion chamber for ignition. Generally, these designs are achieved through additive manufacturing, and would be extremely difficult, if not impossible, to be manufactured using traditional techniques.

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.