Abstract: A conversion mechanism for selective conversion of a conventional mechanical fuel pump computer to selectively extend the unit volume price range of the computer while maintaining the rotational speed of the right hand cost counter wheels of the computer within acceptable limits. The conversion mechanism comprises a cost drive ratio selector mechanism and one or more sets of substitute single transfer and double transfer right hand cost counter wheels and provides for selectively and successively shifting the decimal point of the unit volume price range and cost counter readout and for establishing a cost counter drive ratio for each of the substitute right hand cost counter wheels.

Abstract: A modified mechanical gasoline pump computer with an input gear box mounted on the underside of the base of the computer variator. A depending gear box input shaft is coupled to be driven by the gasoline meter and is axially shiftable for axially shifting gear box output gearing mounted on the variator center shaft upwardly from a gallon unit volume measure gear ratio setting to an alternate quart or liter unit volume measure gear ratio setting.