Fiat A.12bis

A.12
Preserved Fiat A.12 engine
Type	Piston engine
Manufacturer	Fiat
Number built	13,260
Developed from	Fiat A.10

The Fiat A.12 was a six-cylinder liquid-cooled in-line engine with a bore of 160 mm and a stroke of 180 mm, giving a capacity of just under 22 liters, with variants producing between 245 and 300 horsepower at 1,700 rpm. The A.12 was a rather large aero engine at the time and its dimensions were more typical of a marine engine, but it was efficient and reliable. No doubt Fiat's experience with large racing engines contributed to its success. A total of 13,260 A.12s were produced between 1916 and 1919.

Data from

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Wikipedia