Abstract: Apparatus is provided for use in an internal combustion engine for increasing the efficiency of the engine and more particularly for improving the carburation of fuel supplied to the engine. The apparatus includes the combination of a heat exchanger in the fuel line for heating liquid fuels supplied to the engine carburetor, a plurality of deflecting blades positioned adjacent to the carburetor air intake for causing turbulation of air entering the carburetor, and an air injector for forcing air into the carburetor throat downstream of the carburetor Venturi section and to increase the proportion of air in the fuel mixture.