A throttle body assembly for a combustion engine includes a throttle body having a pressure chamber including a supply of liquid fuel, and a throttle bore with an inlet through which air is received. A throttle valve is carried by the throttle body with a valve head movable relative to the throttle bore. A metering valve is coupled to the throttle body, and has a valve element that is movable between open and closed positions. A boost venturi is located in the throttle bore and has an inner passage that is open at both ends to the throttle bore. The boost venturi has an opening through which fuel flows into the inner passage when the valve element is in the open position, wherein fuel flows from the pressure chamber to the metering valve under the force of gravity or under a pressure of less than 6 psi.

A throttle body assembly for a combustion engine includes a throttle body having a pressure chamber including a supply of liquid fuel, and a throttle bore with an inlet through which air is received. A throttle valve is carried by the throttle body with a valve head movable relative to the throttle bore. A metering valve is coupled to the throttle body, and has a valve element that is movable between open and closed positions. A boost venturi is located in the throttle bore and has an inner passage that is open at both ends to the throttle bore. The boost venturi has an opening through which fuel flows into the inner passage when the valve element is in the open position, wherein fuel flows from the pressure chamber to the metering valve under the force of gravity or under a pressure of less than 6 psi.

A throttle body assembly for a combustion engine includes a throttle body having a pressure chamber including a supply of liquid fuel, and a throttle bore with an inlet through which air is received. A throttle valve is carried by the throttle body with a valve head movable relative to the throttle bore. A metering valve is coupled to the throttle body, and has a valve element that is movable between open and closed positions. A boost venturi is located in the throttle bore and has an inner passage that is open at both ends to the throttle bore. The boost venturi has an opening through which fuel flows into the inner passage when the valve element is in the open position, wherein fuel flows from the pressure chamber to the metering valve under the force of gravity or under a pressure of less than 6 psi.

A throttle body assembly for a combustion engine includes a throttle body having a pressure chamber including a supply of liquid fuel, and a throttle bore with an inlet through which air is received. A throttle valve is carried by the throttle body with a valve head movable relative to the throttle bore. A metering valve is coupled to the throttle body, and has a valve element that is movable between open and closed positions. A boost venturi is located in the throttle bore and has an inner passage that is open at both ends to the throttle bore. The boost venturi has an opening through which fuel flows into the inner passage when the valve element is in the open position, wherein fuel flows from the pressure chamber to the metering valve under the force of gravity or under a pressure of less than 6 psi.

A throttle body assembly for a combustion engine includes a throttle body having a pressure chamber including a supply of liquid fuel, and a throttle bore with an inlet through which air is received. A throttle valve is carried by the throttle body with a valve head movable relative to the throttle bore. A metering valve is coupled to the throttle body, and has a valve element that is movable between open and closed positions. A boost venturi is located in the throttle bore and has an inner passage that is open at both ends to the throttle bore. The boost venturi has an opening through which fuel flows into the inner passage when the valve element is in the open position, wherein fuel flows from the pressure chamber to the metering valve under the force of gravity or under a pressure of less than 6 psi.

A throttle body assembly for a combustion engine includes a throttle body having a pressure chamber including a supply of liquid fuel, and a throttle bore with an inlet through which air is received. A throttle valve is carried by the throttle body with a valve head movable relative to the throttle bore. A metering valve is coupled to the throttle body, and has a valve element that is movable between open and closed positions. A boost venturi is located in the throttle bore and has an inner passage that is open at both ends to the throttle bore. The boost venturi has an opening through which fuel flows into the inner passage when the valve element is in the open position, wherein fuel flows from the pressure chamber to the metering valve under the force of gravity or under a pressure of less than 6 psi.

In at least some implementations, a throttle body assembly for a combustion engine includes a throttle body having a pressure chamber in which a supply of fuel is received and a throttle bore with an inlet through which air is received, a throttle valve carried by the throttle body with a valve head movable relative to the throttle bore to control fluid flow through the throttle bore, and a metering valve carried by the throttle body. The metering valve may have a valve element that is movable between an open position wherein fuel may flow from the pressure chamber into the throttle bore and a closed position where fuel is prevented or substantially prevented from flowing into the throttle bore through the metering valve.

In at least some implementations, a throttle body assembly for a combustion engine includes a throttle body having a pressure chamber in which a supply of fuel is received and a throttle bore with an inlet through which air is received, a throttle valve carried by the throttle body with a valve head movable relative to the throttle bore to control fluid flow through the throttle bore, and a metering valve carried by the throttle body. The metering valve may have a valve element that is movable between an open position wherein fuel may flow from the pressure chamber into the throttle bore and a closed position where fuel is prevented or substantially prevented from flowing into the throttle bore through the metering valve.

A fuel discharge nozzle for discharging fuel into an airflow passageway of a barrel of a carburetor includes a nozzle body that is attached to the carburetor and has proximal and distal ends. The nozzle body defines a fuel inlet that receives fuel, a fuel outlet that permits the fuel to flow out of the nozzle body, and a fuel passage fluidly connecting the fuel inlet and the fuel outlet so that the fuel can flow from the fuel inlet to the fuel outlet. The nozzle body is sized and shaped to position the fuel outlet in the airflow passageway of the barrel of the carburetor when the nozzle body is attached to the carburetor so that the fuel flows into the airflow passageway of the carburetor and mixes with air after the fuel flows out of the fuel outlet.

A fuel discharge nozzle for discharging fuel into an airflow passageway of a barrel of a carburetor includes a nozzle body that is attached to the carburetor and has proximal and distal ends. The nozzle body defines a fuel inlet that receives fuel, a fuel outlet that permits the fuel to flow out of the nozzle body, and a fuel passage fluidly connecting the fuel inlet and the fuel outlet so that the fuel can flow from the fuel inlet to the fuel outlet. The nozzle body is sized and shaped to position the fuel outlet in the airflow passageway of the barrel of the carburetor when the nozzle body is attached to the carburetor so that the fuel flows into the airflow passageway of the carburetor and mixes with air after the fuel flows out of the fuel outlet.