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 an 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.

Apparatus and method for directing airflow into the air intake (carburetor or fuel injection system) of an internal combustion engine for increasing air flow velocity and the quantity of air reaching the cylinder or cylinders thereof through the use of an electrically powered fan, are described. The fan is installed inside of the air filter element such that when the air intake throttle plates are closed or partially closed, the unused airflow exits the apparatus to relieve the pressure created by the fan, and when additional air is needed by the engine, air can enter the filter element. The fan may be continuously operated during the operation of the motor, and at all engine speeds.

Disclosed is a vehicle. The vehicle generally includes a frame to support an engine and one or more ground supports, such as wheels, to support the frame. The engine may include an internal combustion power plant and a fuel supply system therefore.

A supercharging and stabilizing structure for an all terrain vehicle or a utility vehicle includes an engine body including a cylinder having an intake passage and an outtake passage. A supercharger includes a chamber having an inlet and an outlet. The supercharger further includes a duct at the inlet. An air accumulator is mounted between the cylinder and the supercharger and includes an air chamber. An input side of the air chamber intercommunicates with the outlet and the duct of the supercharger. An intake manifold is connected between an output side of the air chamber and the intake passage. When fuel is added into an engine, a control valve on the duct is closed. During fuel return or idling of the engine, the control valve is opened, and the inlet and the outlet of the supercharger, the air chamber, and the duct intercommunicate with each other to balance pressure.

A throttle body fuel injection system including a throttle body with at least one air intake, a fuel injector coupled to the throttle body at a fuel port and an annular ring coupled to the cylindrical inner wall of the air intake. The annular ring includes a primary fuel discharge orifice adjacent to the fuel port and a plurality of secondary fuel discharge orifices arranged radially around the annular ring for spraying atomized fuel into the air intake.

An air intake structure of a saddle riding vehicle disposed on a saddle riding vehicle that includes intake system components above an engine, the engine includes a plurality of cylinders aligned at least in front and rear, the intake system components include: funnels coupled to intake ports of the respective cylinders; and injectors facing openings of the respective funnels, the funnels and the injectors are arranged inside the air box, the air intake structure includes an air filter in a front side with respect to the funnel and the injector disposed in a cylinder in a front side. In the air intake structure of a saddle riding vehicle, the air filter is at least disposed so as to be oriented in a vertical direction in side view, and the air filter has a middle part on which a louver is disposed.

Internal combustion engines having an external mixture formation and compensation tank for avoiding reignition. An internal combustion engine is provided having an external mixture formation including at least one exhaust system, at least one intake system, the intake system including at least one intake manifold, at least one throttle valve, at least one mixture forming device, at least one compensation tank, and at least one air filter.

An apparatus and a method are provided for an air intake assembly configured for use with Pro Stock vehicles comprising fuel injection equipped engines. The air intake assembly comprises an air inlet that includes a distal opening disposed in a forward direction at a front of the vehicle and configured to direct incident air into the air intake assembly. An air duct is joined with the air inlet by way of a first coupler configured to maintain an airtight seal between the air inlet and the air duct. A throttle body adapter is joined with the air duct by way of a second coupler configured to maintain an airtight seal therebetween. The throttle body adapter is configured to establish an airtight coupling between the air intake assembly and a throttle body of the engine, such that the incident air is directed into the throttle body.

An intake manifold includes: multiple branch pipes having downstream ends fastened to a front or rear surface of a cylinder head; a main pipe connected to upstream ends of the branch pipes; and a cover including a cover main body attached to an upper surface of a portion of at least one of the branch pipes to define a blow-by gas passage, and a protrusion protruding upward from the cover main body, the portion of the at least one of the branch pipes being adjacent to the cylinder head, wherein the protrusion is spaced apart from the cylinder head in a fore and aft direction such that a fuel line positioned above the downstream ends of the branch pipes is interposed between the protrusion and the cylinder head in the fore and aft direction, the protrusion being positioned to overlap a part of the fuel line as seen from front.

Apparatuses, systems, and methods are disclosed to produce HHO gas in a pressure-resistant container for use in an internal combustion engine to increase fuel efficiency and/or reduce emissions, for example by introducing the HHO gas to one or more air intake ports of the engine.