Abstract: Various embodiments of the present invention are directed to a system and method for increasing fuel efficiency in internal combustion engines by radially accelerating fuel prior to combustion. In one embodiment of the present invention, fuel is input, under pressure, to an enclosed fuel-acceleration chamber between a rotating rotor and stationary rotor housing. While in the acceleration chamber, the rotating rotor radially accelerates the fuel and the acceleration, in turn, may generate turbulence or cavitation within the fuel. The fuel is then output from the fuel-acceleration chamber to a treated-fuel reservoir and to a fuel-combustion site.