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Both engines were good and probably could have been placed into mass production.
No manufacturer was able to get more than two cylinders per crank pin to work at the the rpm and boost levels of a liquid cooled engine after any reasonable development period, the Vulture and the Jumo 222 being the two prime examples.
I favor the two crankshaft 24 cylinder engines. I think we would have had a winner if Rolls Royce had built the Vulture as a two crankshaft engine. Two side by side 120 degree bank angle V-12s on one crankcase. Not much wider than the historic single crank Vulture, I feel it still would have fit into the Hawker Tornado.
Don't forget that Rolls Royce investigated doubling the Merlin, 24 cylinders and two crankshafts in a single crankcase casting in a vertical H arrangement, with standard Merlin cylinder blocks. Had a good chance of being a winner. 2400 reliable HP early in the war, 3000 HP by 1944, and 4000+ HP before V-J day. It would have been an interesting upgrade for the Avro Manchester. The Shackleton could have been two engines, like the American P2V Neptune.
The Wright engine was about 2180 cu in. They were trying for High speed. The engine was supposed to be modular and could be stacked in 14 cylinder groups.
It was a complete waste of time and money.