Abstract: A carburetor system for use in combination with an internal combustion engine or the like wherein the fuel from the usual fuel pump is directed into a heating chamber through jets wherein the fuel is atomized upon entry into the chamber, and the atomized fuel is heated to a substantially complete vapor state prior to injection into the venturi of the carburetor. The hot fuel vapor enters the air stream in the venturi for mixing therewith whereupon the fuel-air mixture is directed to the manifold and combustion chamber for burning thereof. The fuel is delivered to the venturi through an orifice which is controlled in direct relation with the throttle valve of the carburetor whereby the air-fuel ratio is maintained at an optimum operation standard through the entire engine operating range.