Abstract: A fuel preconditioner for catalytic cracking of long-chain liquid hydrocarbons, and particularly gasoline, for internal combustion engines. A tubular housing, in-line with the fuel pump and carburetor or fuel injection system, contains a platinum catalyst for the cracking of liquid hydrocarbons into more volatile components for superior combustion, Heater elements may be provided for acceleration of the catalytic action. In one embodiment, the tubular housing defines a fuel rail of a fuel injection system.