The initial engine was the Wright R-3350-23 Cyclone. This engine had 9 cylinders in 2 rows, for a total of 18 cylinders. The engine was air-cooled and had an unfortunate tendency to catch fire. (At every engine start, a ground crewman stood by with a fire extinguisher. His role was more than symbolic.) The engine had 2 turbo-superchargers for high altitude performance. The takeoff power was 2,200 hp. The war-emergency power was 2,300 hp at 25,000 ft.

Wright attempted to cure the overheating problems with the R-3350-41. This engine had baffles and oil crossover pipes. The last B-29s had the R-3350-57 engine.

As the ad indicates, Dodge also made Wright Engines. However, air crews seemed to have a lot of fuel problems with the Dodge engines.