The Bitter CD is a car produced between 1973 and 1979. It was sold as a 3-door hatchback coupe with rear-wheel drive and a front-mounted engine. It was first introduced to the public as a prototype in September 1969 at the Frankfurt Motor Show under the name Opel Coupé Diplomat.
After a positive response to the prototype, the decision was made to mass produce it. The car was to have a conventional door opening system, windscreen wipers and other parts derived from the Opel Diplomat to facilitate production. The car was powered by a 5.3-litre V8 engine with 230 hp (169 kW). In total, just under 400 examples were produced.
