Abstract: Pre-cooled aerosol spray fuel/air mixture is discharged through an array of metering tubes which are housed within a heat exchange chamber. Engine coolant is circulated through the heat exchange chamber. As the aerosol fuel/air mixture is drawn from the carburetor through the metering tubes and into the manifold, heat transfer from engine coolant circulating through the heat exchange chamber causes the aerosol mixture in the metering tubes to vaporize. In a preferred embodiment, the temperature rise within the heat exchange chamber is limited by heat transfer to an air circulation tube which is coiled within the heat exchange chamber.