Can anyone tell me the horsepower rating of an Army generator engine? I have one that is dated January 1952, as best as I can tell. I am going to put it in my project car. I don't have a clue on it's specs. I was hoping someone might have some information on one.

One of my generator engine has a plate on the water jacket that gives slightly lower compression numbers than a standard car engine and lists 21HP. I have a different generator engine in an FOR. It doesn't have the plate. It doesn't feel that much different than other Crosley engines for power. Not sure if it is also 21hp or if there were different ratings for different generator engines.

Update 6-2026 - Most/all generator engine have a plate under the block to lower the compression so it will run on the lower quality of fuel that may be found in army field use. If you want the full power and you have a plate it should be removed to get the intended compression for civilian use.