I was happy to see there was another P-51 Mustang at the Museum of Aviation at Robins Air Force Base in Georgia. This one was called “Ferocious Frankie”. It had an American version of the famous British Rolls Royce Merlin V-12 engine that also powered the Spitfires and Hurricanes of the Battle of Britain in 1940.
These engines were produced by Packard in the United States. These new engines were 1300 hp and 1647 cubic inches in size weighing 1,400 pounds and costing $25,000. More than 16,000 Merlin V-12 engines were built by Packard in the Detroit, Michigan by the end of the war. At the end of World War II, the British were using the Packard built Merlins in their Spitfires, Mosquitos and Lancaster planes. I have heard that these engines were used after the war even in high end speed boats.