When the new Formula One regulations stipulated a limit of 2½ litres Ferrari found that the 553 Squalo in 1954 and 555 Supersqualo in 1955 were not fast or reliable enough to beat the Mercedes Benz W196 and Maserati 250Fs. They reverted in some races to the older Ferrari 625 which was basically the 2 litre Formula Two 500 of 1952/53 with a lengthened chassis and fitted with a 2½ litre engine. One of these cars took part in the SeeRed meeting at Donington Park in September 2007.
It's Alexander Boswell's car and was apparently fitted with a 3 litre engine at this time.
At the end of the 1955 season the Lancia team withdrew from racing due to financial difficulties and Ferrari took over their D50 F1 cars, racing them for the next two seasons with various degrees of modification. They took Fangio to the World Championship title in 1956 but weren't very successful the following season.