Abstract: A fuel and air induction system is provided for an internal combustion engine and includes a conventional air and fuel mixing carburetor for starting the engine when cold. However, when operating temperatures of the engine are obtained the air and fuel induction system is operative to substantially fully vaporize liquid fuel by heating the induction air and spraying fuel into the heated induction air in a manner that completely vaporizes the fuel and this vaporized fuel is then mixed with supplemental induction air which has also been heated and passed through the conventional carburetor into the intake passages of the engine, the supply of liquid fuel to the carburetor being terminated after operating temperatures of the engine are achieved.