However, it was not just the Ingolstadt manufacturing facility that Volkswagen acquired from Mercedes when they purchased the Auto Union business. Among the employees inherited from the Mercedes era was engineer Ludwig Kraus. Kraus did not share Nordhoff’s apparent conviction that demand for the Beetle would remain insatiable for ever, and it was Kraus who developed the Audi 100, in direct contravention of instructions from Volkswagen management, and in secret. The first Nordhoff knew of the project was when he was presented with a production ready prototype. It is to Nordhoff’s credit that he changed his mind and gave the car the green light. The Audi 100 would be a commercial success, but it would also be the first of a series of front engined water cooled Audi based designs from the Volkswagen group that would, starting with the first Passat in 1973, enable the group to survive and flourish once the European and US markets began to lose their appetites for rear engined air cooled models.
The Audi 100 was shown to the press on 26 November 1968. Its name originally denoting a power output of 100PS (99hp/74kW), the Audi 100 was the company's largest car since the revivial of the Audi brand by Volkswagen in 1965. The C1 platform spawned several variants: the Audi 100 two- and four-door saloons, and the Audi 100 Coupé S, a stylish fastback coupé, which bore a remarkable resemblance to the Aston Martin DBS released a year earlier, especially at the rear end, including details such as the louvres behind the rear side windows and shape of the rear light clusters.
Audi followed up the introduction of the four-door saloon in November 1968 with a two-door saloon in October 1969 and the 100 Coupé S in autumn 1970. The cars' four-cylinder engines originally came in base (1.8 litre, 80PS (79hp/59kW)), 100 S (1.8 litre, 90PS (89hp/66kW)) and 100 LS (1.8 litre, 100PS (99hp/74kW)) guise, while the Coupé was driven by a bored-out 1.9 litre developing 115PS (113hp/85kW). From April 1970 the 100 LS could be ordered with a 3-speed automatic transmission sourced from Volkswagen.