"Which Fiat Was This?"
Your mention (August, 1974) of the Openshaw Fiat puzzles me frankly, and 1 very much wonder if it was a "real" racing car (Fiat themselves looked upon the S61 as a sports model).
I don't think that it can have been a Vintage machine as Fiat themselves say categorically that the last works team cars to be sold into private ownership were the S57 Grand Prix types of 1914, by this time bored out to 4,859 c.c. as a result of the company's abortive plans to run at Indianapolis in 1917. They did not all, incidentally, have the modified tails in 1919, and the car campaigned that year by Antonio Ascari was still a 4litre. I think, but would not like to prove, that the cars were sold by the factory some time in 1921; certainly no works driver is on record as having handled one during the 1922 season.
However, I agree with you that somebody Would surely have noticed or remembered the presence of an S57 of any type in England in the 1920s, so let's try another theory, in the shape of the odd o.h.c. cars made for the 1910 Prince Henry Trials. These were not racers, and they don't appear in any publication (even mine), quite simply because up to now nobody has sorted them out. These were shaft-driven, and had four-cylinder monobloc o.h.c. engines of 95 x 155 mm. The engine designation was S53A and this unit was also fitted to some special editions of the Tipo 3TER sports-tourer. This combination of engine and chassis was almost certainly used in the 1912 and 1913 Targa Florios, by the way.
One more tantalising clue. In 1911 Capt. Theo Masui, then the German concessionaire in London, took delivery of a car which looks very like a Prince Henry model, which he fitted with a sporting torpedo body of his own design. The Autocar, however, quotes Cylinder dimensions of 95 x 170 mm. for this one and, further, Openshaw specifically said that he bought his in Italy. So it can't be the ex-Masui machine!
It would be interesting to know if the Openshaw car had shaft or chain drive, in Which connection it is worth remembering that the S61 was made with both—to the customer's choice.
One thing is certain: that up to 1911, if not slightly later, Fiat were prepared to build special racing variations to customer's order. That these didn't always appear in catalogues Is probably due to the fact that the American stock-car racing craze was over by 1910, and hence no form of homologation, however localised, was necessary.
Midhurst Michael Sedgwick