i can't find that temp article... but here is something i found on the web...
"Screw type superchargers are derived from the Roots type concept but with vast improvements for street use. Although from the out side, screw type superchargers may look a lot like Roots type superchargers, on the inside you will find a twin-screw design that compresses air unlike Roots type superchargers which pump the air into the motor. Screw type superchargers have an axial-flow design that compresses the air as it moves between the screws to create positive pressure without creating the heat that Roots type superchargers can create. The Screw type supercharger's ability to produce a dramatic increase of power from idle and through out the rest of the power curve make them a great choice for heavy vehicles, towing or commercial use. "