Opel straight-6 engine

Opel used the straight-6 engine configuration for many years. Opel used two straight-6 engines prior to the better-known CIH engine family.

Moonlight
The Opel Moonlight roadster was the first Opel vehicle with a straight-6. It used a 1790 cc six in 1933. It was a 12-valve engine with a very-undersquare 65x90 mm bore and stroke, typical for the time. This engine produced 33.5 PS and 100 Nm.

Kapitän
The 1959 Opel Kapitän was the next vehicle from the company with a straight-6 engine. This was a 2605 cc unit with 12 overhead valves. Bore and stroke were now oversquare for high power output at 85x76.5 mm. A single Opel-designed carburetor and 7.8:1 compression yielded 91 PS and 186 Nm.