A metal valve body having a fuel injection port includes a nozzle plate accommodation part accommodating a nozzle plate of synthetic resin and aligning a center of the nozzle plate with a central axis of the valve body. A front end surface abutting against the nozzle plate is accommodated in the nozzle plate accommodation part. A swage projection fixes the nozzle plate to the front end side on which the fuel injection port is formed. The nozzle plate is swage-fixed in the state in which a spring action part is elastically deformed on the front end side of the valve body by the swage projection, and a nozzle hole formation part is constantly pushed against the front end surface of the valve body by the elastic force of the spring action part.

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.

Present embodiments provide a throttle body which may be used with a variety of engines of different manufacturers. The throttle body may be used to replace mechanical or hydraulically controlled carburetors with electronic fuel injection. The throttle body may provide improved fuel pathways through and about the throttle body in order to move fuel to opposed side. The throttle bodies may have improved configuration of the fuel injectors. Further, the throttle body may have computer mounted on the throttle body and a notch formed in the throttle body to define a wire routing pathway from the computer to the injectors.

An electronic fuel injection throttle body unit has a core body with two side components. The two side components each including a fuel delivery passage. Four air intake passages extending vertically through the throttle body. Valves are rotatable within the air intake passages. The valves being connected to valve shafts that rotate about respective valve shaft axes. The valve shaft axes and the fuel delivery passages are perpendicular to each other.

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 electronic fuel injection throttle body unit has a core body with two side components. The two side components each including a fuel delivery passage. Four air intake passages extending vertically through the throttle body. Valves are rotatable within the air intake passages. The valves being connected to valve shafts that rotate about respective valve shaft axes. The valve shaft axes and the fuel delivery passages are perpendicular to each other.

A fuel injection throttle body assembly for an internal combustion engine and including a throttle body case defining a port. The fuel injection throttle body assembly further includes a fuel distribution sleeve disposed in the port and a throttle valve pivotably supported by the throttle body case and disposed in the port. The throttle valve is arranged between the fuel distribution sleeve and the outlet side of the throttle body case. The fuel distribution sleeve includes an annular body extending from a first sleeve end to a second sleeve end and has an inlet portion proximate the first sleeve end defining an inlet diameter, an outlet portion proximate the second sleeve end defining an outlet diameter, and a throat portion positioned between the inlet portion and the outlet portion defining a throat diameter, wherein the throat diameter is less than the inlet diameter and the outlet diameter.

A method of using a throttle body fuel injection system including a throttle body with at least one air intake, an electronic 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 fuel discharge orifices arranged radially around the annular ring for spraying atomized fuel into the air intake, in order to operate an internal combustion engine.

A fuel injection throttle body assembly for an internal combustion engine and including a throttle body case defining a port. The fuel injection throttle body assembly further includes a fuel distribution sleeve disposed in the port and a throttle valve pivotably supported by the throttle body case and disposed in the port. The throttle valve is arranged between the fuel distribution sleeve and the outlet side of the throttle body case. The fuel distribution sleeve includes an annular body extending from a first sleeve end to a second sleeve end and has an inlet portion proximate the first sleeve end defining an inlet diameter, an outlet portion proximate the second sleeve end defining an outlet diameter, and a throat portion positioned between the inlet portion and the outlet portion defining a throat diameter, wherein the throat diameter is less than the inlet diameter and the outlet diameter.

An electronic fuel injection throttle body unit has a core body with two side components. The two side components each including a fuel delivery passage. Four air intake passages extending vertically through the throttle body. Valves are rotatable within the air intake passages. The valves being connected to valve shafts that rotate about respective valve shaft axes. The valve shaft axes and the fuel delivery passages are perpendicular to each other.