With the Chevrolet V8 under the hood, the drive system of the top model also matched the American look of Opel's new three-seater. But unlike the conventional US models, it also had a chassis that could cope with the power, as well as decent brakes. In addition, the automatic transmission raised ride comfort to a completely new level by European standards. This historical test report identifies the strengths and weaknesses of the Opel Diplomat V8.