Opel Diplomat B Cabriolet

The Opel Diplomat Cabriolet was a four-door convertible based on the Opel Diplomat B and produced in a series of four cars in 1971. The project was commissioned by Opel during the winter of 1970–1971 as a group of representation vehicles. Opel initially placed the order with Karmann in Osnabrück, which subcontracted the body conversion to Carrozzeria Fissore in Savigliano, Italy. Four Diplomat saloons, finished in white, blue, silver and gold, were sent to Fissore. The Italian coachbuilder removed the steel roof and converted the four-door bodies into open cars, adding structural reinforcements to compensate for the loss of the original roof structure. The side windows and their frames were retained. After completion of the structural work, the cars were transported to Karmann in Osnabrück. Karmann carried out the final painting, installed the leather interiors and completed the folding soft top. The roof was operated by an electro-hydraulic system using components supplied by Cadillac in the United States. The conversion cost approximately 70,000 Deutsche Mark per car. Including the donor vehicle, the total cost approached 100,000 Deutsche Mark, compared with approximately 19,000 DM for a standard Diplomat B at the time. The Cabriolets retained Opel’s 2,784 cc inline six-cylinder engine with Bosch electronic fuel injection, producing 165 PS (121 kW). Power was transmitted through a three-speed automatic gearbox. The cars also retained the Diplomat’s De Dion rear suspension and four-wheel disc brakes. Opel quoted a maximum speed of 175 km/h for the Cabriolet. From 1971 to 1980, the four cars were used at public events. They served as parade vehicles, including during the Mainz Rosenmontag procession, and were also used at Formula One events at the Nürburgring and Hockenheimring. The example currently documented by Opel Classic was the last of the four completed and was registered by Adam Opel AG in August 1971. It was sold to an Opel dealer in Mainz in 1980, passed to another Opel dealer in Illingen an der Saar in 2005, and has been owned by Heiner Schnorrenberg since 2025.