This is the Admiral upgraded with eight cylinders. Why not, the mother company GM has enough V8 engines on offer. In the first year this engine is left exclusively to the Diplomat. Outwardly the Diplomat is recognizable by its vertical front headlights, and its vinyl roof. Because the car is relatively dark inside, the interior might warm up excessively in summer. But the Americans love it. The power steering and power windows are uncommon at that time.The interior is a little homier, the instrument cluster more functionally. There will never again be such a large Opel sedan. Why is the KAD series in spite of its favorable price not successful? Maybe because they do not look like European cars? They might be considered too large and without personal trademark. It is not possible to regard them as extension or expression of one's personality. The American managers of GM did not take into consideration that these cars are considered upper class vehicles in Europe. They are looked upon as extension of the buyer's own personality. The KAD series is too rationally. Someone who has made it simply buys a Mercedes. In 1969 the second attempt is undertaken with a larger V8 engine from the coupe and optionally six-cylinders. The car body is reduced a bit in size, but extraordinary are the chassis changes. The huge space in the rear below the car body suffices for a De Dion axis. Finally, the chassis is level with the huge engine power. Admittedly, the car weight clearly increases. It is a pity, but in spite of all the efforts, and the fact that the result is definitely competitive, the car is no sales success.