Abstract: A fuel-air mixing device for installation preferably between an intake manifold and air intake duct of a cylinder of an internal combustion engine. The device extends downstream into the air intake duct, and has an open inlet end for channeling the air-fuel mixture into the device. A closed downstream end forces the air-fuel mixture to flow into the downstream end of the intake duct via special apertures which are adapted to atomise the fuel and mix the same with air. The arrangement ensures that the air-fuel mixture is urged towards the along the walls of the air intake duct, thereby vaporising the fuel by thermal contact therewith.