A mass air flow measurement apparatus for an internal combustion engine includes: a plurality of pressure sensors disposed at different locations along an air intake path of the internal combustion engine, each pressure sensor adapted to sense a pressure of air flowing into the internal combustion engine and output an electrical signal as a pressure signal corresponding to the sensed air pressure; a carburetor having a plurality of booster venturis, the carburetor rendered permanently inoperable to mix fuel with air flowing in the air intake path, a body of the carburetor configured to accept one or more of the plurality of pressure sensors for each of the plurality of booster venturis; and a calculation section that receives the pressure signals and generates a mass air flow signal as an output signal to an engine management system to control an electronic fuel injection system based on the received pressure signals.

A mass air flow measurement apparatus for an internal combustion engine includes: a plurality of pressure sensors disposed at different locations along an air intake path of the internal combustion engine, each pressure sensor adapted to sense a pressure of air flowing into the internal combustion engine and output an electrical signal as a pressure signal corresponding to the sensed air pressure; a carburetor having a plurality of booster venturis, the carburetor rendered permanently inoperable to mix fuel with air flowing in the air intake path, a body of the carburetor configured to accept one or more of the plurality of pressure sensors for each of the plurality of booster venturis; and a calculation section that receives the pressure signals and generates a mass air flow signal as an output signal to an engine management system to control an electronic fuel injection system based on the received pressure signals.

A mass air flow measurement apparatus for an internal combustion engine includes: a plurality of pressure sensors disposed at different locations along an air intake path of the internal combustion engine, each pressure sensor adapted to sense a pressure of air flowing into the internal combustion engine and output an electrical signal as a pressure signal corresponding to the sensed air pressure; a carburetor having a plurality of booster venturis, the carburetor rendered permanently inoperable to mix fuel with air flowing in the air intake path, a body of the carburetor configured to accept one or more of the plurality of pressure sensors for each of the plurality of booster venturis; and a calculation section that receives the pressure signals and generates a mass air flow signal as an output signal to an engine management system to control an electronic fuel injection system based on the received pressure signals.

A mass air flow measurement apparatus for an internal combustion engine includes: a plurality of pressure sensors disposed at different locations along an air intake path of the internal combustion engine, each pressure sensor adapted to sense a pressure of air flowing into the internal combustion engine and output an electrical signal as a pressure signal corresponding to the sensed air pressure; a carburetor having a plurality of booster venturis, the carburetor rendered permanently inoperable to mix fuel with air flowing in the air intake path, a body of the carburetor configured to accept one or more of the plurality of pressure sensors for each of the plurality of booster venturis; and a calculation section that receives the pressure signals and generates a mass air flow signal as an output signal to an engine management system to control an electronic fuel injection system based on the received pressure signals.

A mixing manifold is provided. The manifold includes: a body; a first converging passageway in the body; a first diverging passageway in the body in-line and in fluid communication with the first converging passageway to form a first venturi; a first obstruction in a throat of the first venturi configured to move between two positions, a blocking position that blocks, at least in part, flow through the first venturi and an open position; a second converging passageway in the body; a second diverging passageway in the body in-line and in fluid communication with the second converging passageway to form a second venturi; and a second obstruction in the second venturi configured to move between two positions, a blocking position that blocks, at least in part, flow through the second venturi and an open position. A method of providing fluid flow through a manifold is also provided.

A mixing manifold is provided. The manifold includes: a body; a first converging passageway in the body; a first diverging passageway in the body in-line and in fluid communication with the first converging passageway to form a first venturi; a first obstruction in a throat of the first venturi configured to move between two positions, a blocking position that blocks, at least in part, flow through the first venturi and an open position; a second converging passageway in the body; a second diverging passageway in the body in-line and in fluid communication with the second converging passageway to form a second venturi; and a second obstruction in the second venturi configured to move between two positions, a blocking position that blocks, at least in part, flow through the second venturi and an open position. A method of providing fluid flow through a manifold is also provided.

A mass-airflow measurement conversion apparatus for internal combustion engine carburetors includes a plurality of pressure sensors disposed at different location along an air intake path of an internal combustion engine, each sensor adapted to sense a pressure of air flowing into the internal combustion engine and output an electrical signal as a pressure signal corresponding to the sensed air pressure; and a calculation section that receives the pressure signals and generates a mass air flow signal as an output signal based on the received pressure signals.

A gaseous fuel and air mixing venturi device is adapted for installation in a gaseous fuel carburetor and has a venturi body defining annular inner and outer venturi passageways which each have a throat of reduced cross-sectional area and have inlet ends in communication with an air inlet of the carburetor. A fuel inlet is configured for connection to a fuel port of the carburetor, and communicates with a plurality of fuel supply ports in the body communicating radially with the inner and outer venturi passages to mix with the air flowing in the passageways.

A gaseous fuel and air mixing venturi device is adapted for installation in a gaseous fuel carburetor and has a venturi body defining annular inner and outer venturi passageways which each have a throat of reduced cross-sectional area and have inlet ends in communication with an air inlet of the carburetor. A fuel inlet is configured for connection to a fuel port of the carburetor, and communicates with a plurality of fuel supply ports in the body communicating radially with the inner and outer venturi passages to mix with the air flowing in the passageways.