The NSU Prinz evolved into the somewhat larger bodied NSU Prinz 1000 (Typ 67a), introduced at the 1963 Frankfurt Motor Show. A sporting NSU 1000 TT (with a 1.1 litre engine) also appeared, which was later developed into the NSU (1200) TT and NSU TTS models. All had the same body with inline-four air-cooled OHC engines and were frequently driven as sports cars, but also as economical family cars as well. The mostly alloy engines were very lively, and highly reliable.The OHC arrangement was quite advanced for the time on a small family car as most home-grown cars were still using less efficient pushrod engines. Paired with the low total weight, excellent handling and cornering, both the NSU 1000 and the much higher powered NSU 1200 TT/TTS outperformed many sportscars. 

The Prinz 1000 lost the "Prinz" part of the name in January 1967, becoming simply the NSU 1000 or 1000 C depending on the equipment. It has 40 PS, while the 1200 TT has 65 PS and the most potent TTS version has 70 PS from only one litre.

The NSU Prinz 1000 TT was built in 14.292 examples between 1965 and 1967, when it was replaced by the bigger engined TT. This, with a 1.2-liter engine, was built until July 1972 for a total of 49.327 examples. The TT can be recognized by its broad black stripe between its headlights.

When NSU was acquired by Volkswagen in 1969, it was merged with Auto Union AG. Auto Union had previously been taken over by VW in 1964 and produced mid-sized cars, resurrecting the Audi marque. The name of the new company changed to Audi NSU Auto Union AG. The small, rear-engined NSUs were phased out in 1973, as production capacity was needed for larger and more profitable Audis. The successor of the NSU Prinz was the front-wheel drive Audi 50, later rebadged Volkswagen Polo.

The NSU Ro 80 is a four-door, front-engine executive sedan manufactured and marketed  from 1967 until 1977.

Noted for innovative, aerodynamic styling by Claus Luthe and a technologically advanced powertrain, the Ro 80 featured a 113 bhp, 995 cc twin-rotor Wankel engine driving the front wheels through a semi-automatic transmission with an innovative vacuum-operated clutch system.

The Ro 80 was voted Car of the Year for 1968 and 37.398 units were manufactured over a ten-year production run, all in a single generation.

The relatively high fuel consumption of the rotary engine worked against the car after the dramatic fuel price rises accompanying the oil crisis of 1973.  In total 37.398 Ro80s were produced during the ten-year production run. Ultimately, it was the contrasting success of the similarly sized Audi 100 that sealed both the fate of the Ro 80, and the NSU brand as a whole within the Auto Union-NSU combine, as parent company Volkswagen began nurturing Audi as its performance-luxury brand in the late 1970s. After the discontinuation of the Ro 80 in 1977, the Neckarsulm plant was switched over entirely to producing Audi's