Abstract: The present invention provides a parallel vaporized fuel system as well as a fuel vaporization apparatus for an internal combustion engine. More specifically, when the parallel vaporized fuel system is applied to vehicles, vaporized fuel is provided for general driving and liquid fuel is supplied as needed for immediate and heavy acceleration. The liquid fuel is generally gasoline, methanol or ethanol wherein the fuel vaporizes at a temperature of 425° F. or less. Fuel is delivered to the engine using the liquid fuel system until an adequate amount of vaporized fuel can be produced for operation of the engine. As vaporized fuel is produced liquid fuel being delivered to the engine proportionately reduced. Thereafter liquid fuel can be supplied to the engine when needed to compensate for the delay in vaporizing liquid fuel. This system can thereby provide improved fuel economy and reduced emissions over vehicles operating entirely from liquid fuel.