Bitter started his car building business in 1971, specifically for the CD. His base was a one acre site in his home town of Schwelm. He didn't have the capital or time to set up his own production facilities, and looked for a proven independent, small scale company to build the CD. He chose Baur of Stuttgart as they produced prototypes and limited production runs for several well known German companies. They possessed the necessary experience, had the capacity to build the car, and their build quality was impressive.

Bitter took the Opel Diplomat chassis in its shortened form as it had been developed for the Opel Styling CD concept car. The shortened chassis was completely re-tuned for the new weight and balance parameters, the coil spring settings were altered, and Bilstein shock absorbers were fitted. The Chevrolet 327 cubic inch V8 used in the Diplomat was adopted without modification.

Bitter was heavily influenced in his design of the CD by the stunning Opel Styling CD of 1969 and Frua's more practical interpretation shown at Frankfurt in 1970. These cars offered exotic design and a reliable American V8 engine. After his earlier experiences, Bitter had seen that the combination of eye catching styling and reliable, well proven running gear could work. Bitter sought the willing help of Dave Holls, Opel's Head of Styling, in turning the great potential of the Frua CD into a car for the seventies.

Baur's role in building the CD was major. They made the body panels, assembled the shell, trimmed and fitted the interiors, and mated the Diplomat's running gear to the shell.

The CD was introduced at the end of 1973 after a very successful showing at the Frankfurt Motor Show of September 1973. A euphoric Erich Bitter took 176 orders for his stylish new car at the show, but the oil crisis soon after hit his plans for six and most orders were cancelled. Production never reached the 200 cars per year target but by the beginning of 1975 Bitter had built 100 CD's. With the effects of the oil crisis receding, CD sales continued and in 1976 the production of 254 cars (total) was celebrated in a public advertisement : "Wir freuen uns über die Produktion des 254. Wagens".

At the end of production in 1979 Baur had built 395 CD's.