1957-1960 NUOVA500 Piston 66x70mm Engine 479cc Maximum Power 13Hp Weber24IMB 1960-1965 FIAT 500D Piston 67.4x70mm Engine 499.5cc Maximum power 17.5cv Weber26IMB4 1965-1972 Fiat 500F 67.4x70mm 499.5cc 18Hp Weber26IMB4 1968-1972 FIAT 500L 67.4x70mm 499.5cc 18Hp Weber26IMB4 1972-1975 Fiat 500R 73.5x70mm 594cc 18Hp(23Hp) Weber26IMB