Abstract: A fuel vapor generator in the form of a heat conductive member having an elongated U-shaped passageway formed through it. The member is mounted at the exterior of a carburetor venturi. A first open inlet end of the passageway extends through the venturi walls and receives atomized fuel from the main fuel nozzle and a portion of the incoming air. This fuel and air mixture is directed through the passageway where it is heated and the fuel is vaporized. The fuel and air are drawn from the passageway and returned into the venturi at a location downstream from the main nozzle. A series of mesh screens extending across the passageway and spaced along its length assist in atomizing the fuel and assuring efficient conduction of heat to the entire mixture of fuel and air within the passageway.