29. 1973 Porsche Carrera 2.7 RS
Built largely for racing after the European GT banned cards above 3 liters, the Porsche Carrera 2.7 was the first to incorporate the maker’s signature rear ducktail spoiler, reducing rear-end lift by 75 percent. To get it suited up for racing, some 100 pounds were dropped off the model, eliminating carpeting, sound deadening, rear seats, clock, interior armrests, and the passenger-side sun visor. It also didn’t have emissions equipment, which kept it out of the US for quite some time.