Saab 96, drag coefficient of 0.37, not bad by 1960's standards. That’s the same, BTW, as a Ferrari F50. A VW Beetle had 0.48, A Citroen DS 0.36.

The original Saab 92, 0f 1949, with its lower roof and gentler rear taper had 0.30, which is still excellent even by current standards. Current model Prius? Only 0.24