How many cylinders does the Duesenberg Model J engine have? The answer is 8.
The Duesenberg Model J used a 420-cubic-inch straight-eight engine. Its eight cylinders were arranged in a single bank, an inline configuration that Duesenberg developed from its successful racing-engine work of the 1920s.
The engine was exceptionally advanced for a luxury car of the late 1920s. It used dual overhead camshafts and four valves per cylinder, producing 265 horsepower in normally aspirated form. Lycoming manufactured the engine for Duesenberg; both companies were connected to industrialist E. L. Cord.
The Model J debuted in 1928 as an ultra-luxury American automobile, with its chassis supplied to specialist coachbuilders for custom bodies. Its straight-eight powerplant could propel the car to about 116 mph, remarkable performance for a heavy luxury car of the period.
The supercharged SJ and later SSJ versions also retained the straight-eight layout. They are sometimes confused with larger-cylinder luxury engines from the era, but the Model J’s defining engine was an eight-cylinder unit—not a V-12 or V-16.