2. Audi 100 (C2, 1976)
The Audi 100 C2, introduced in 1976, pioneered lightweight construction and a sleek, aerodynamic profile, achieving a drag coefficient of 0.30. This design significantly improved fuel efficiency and performance, setting a new standard for sport sedans. Its emphasis on aerodynamics and efficiency continues to influence modern automotive design, highlighting the importance of streamlined forms in enhancing vehicle performance. (audi-mediacenter.com)