After five years of development, the NSU RO 80 was presented to the public at the IAA 1967 as the world's first series production car with a 2-disc Wankel engine. This Wankel engine had the advantages of lower weight, smaller space requirements, smooth running and fewer components than a conventional piston engine with comparable power. The saloon set new standards in roadholding, safety, comfort and performance. The drag coefficient was just 0.35. In 1967, the NSU RO 80 was the first German car to be voted "Car of the Year".
From: http://www.audi.com/me_partner/p_aeau000001/home/experience/audi_history/Evolution_of_the_models.html#source=http://www.audi.com/me_partner/p_aeau000001/home/experience/audi_history/Evolution_of_the_models/1945-1965/nsu_automobile/nsu_ro_80.html&container=layerModal
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