You probably haven’t heard of Bitter, but they do make some truly excellent machines. Comparable with the likes of Bristol here in the UK, Bitter is a German/Austrian premium car manufacturer that creates luxury sports-cars on request. Founded in 1971 by Erich Bitter, the company specializes in rebodying other manufacturer’s vehicles and its initial production was between 1973 and 1989, selling vehicles in Europe and the United States. Thereafter, several prototypes followed with an eye on resuming low-volume production, but none of those plans came to fruition until the launch of the Bitter Vero in 2007.
The Bitter CD, a three-door hatchback coupe featuring a 227hp Chevrolet V8 with a 327ci displacement, was built between 1973-1979.
The CD was first shown in prototype form on 9th September, 1969, at the Frankfurt Auto Show, as the Opel Coupé Diplomat (“CD”) derived from the sedan version. It was designed by Charles M. “Chuck” Jordan (Opel’s Design boss between 1967-1971 and later vice-president of General Motors (GM)) with the assistance of George A. Gallion, David Holls, Herbert Killmer and Hideo Kodama, as well as Erhard Fast (Director of the Opel Designstudios 3 for Advanced Design from 1964). The tail was inspired on a proposal by Erhard Fast’s for the 1969 Opel Aero GT.
Thanks to the positive reaction to the CD prototype, Opel considered developing a production models. The doors would adopt a conventional opening system and the bumper bar, windshield wipers and other parts would be derived from the Opel Diplomat in order to facilitate production and maintain costs. Robert “Bob” Lutz, who was the Head of Opel at the time and was keen to produce the car, commissioned Pietro Frua to advance the concept and produce two road-going prototypes.
In 1971, it was David R. “Dave” Holls (Opel design boss since 1971; previously assistant to Charles M. “Chuck” Jordan) who encouraged Erich Bitter to build the Bitter CD. As a result, Bitter GMBH was formed in 1971 to market the CD. He based his company on a 1-acre (4,000 m2) site in his home town of Schwelm, Germany.
However, because he did not have the necessary capital and other resources to set up his own production facilities, Bitter turned to Baur GMBH in Stuttgart, as a proven independent small-scale manufacturer. He selected them given their ability to produce high-quality prototypes and limited production cars for other German manufacturers.
Bitter based his original CD designs on those of Frua, before making alterations closer to production. The basic design changes to Frua’s CD design vis-à-vis the 1969 Opel CD consisted of a truncated read end, modified windshield and less chrome application. Dave Holls and Opel’s design team supplemented the design with a small front spoiler, larger grille, higher bumper bars and by prolonging upwards the lower edge of the rear side windows across the C pillar to the rear hatch. Final prototype testing was conducted at the Opel Test Facility in Duden, in addition to load duration tests by Bitter at the Hydropulseur facility of Baur.
The Baur team also engaged in significant constructive and production development work, which included manufacturing a hard foam mockup. Their role then extended to manufacturing the CD’s body panels, assembling the shell, interior fitting and trimming as well as installing the Opel Diplomat’s mechanicals.
The Bitter CD was displayed, with great success, at the 1973 Frankfurt Motor Show, where Erich Bitter took 176 orders for his stylish new coupe. However, the oil crisis at the time led to the cancellation of most orders. Despite this, production commenced late the same year at Baur GMBH. The target of 200 units/year was never realised and, in total, Bitter sold 395 units. Purchase price in 1974 was 58,400DM.