During the 1930s, Isotta Fraschini had developed a line of air cooled inverted V12 aircraft engines including the 540 hp (403 kW) Gamma.

These proved moderately successful at a time when most Italian aircraft engines were radials, including Isotta Fraschini's own K.14.

[1] In 1939, the Italian air ministry, looking for an appropriate power plant for their next generation of fighter aircraft, approached Germany to license the Daimler-Benz DB 605.

An inverted V12 like the Isotta Fraschini designs, it differed in its liquid cooling but also in its capability, being over twice as powerful as the Italian engines.

Reggiane tested a mock-up in a wind tunnel and mounted it in the nose of a Savoia-Marchetti SM.79 but cooling problems continued to hold development back.