Rules and Bores

Sir,

The usually very accurate D.S.J. says in the May issue that “Until 1934 the cars in the TT, which had to be sports cars, could run stripped of road equipment. . . .” This is only part of the story. The Ulster TT was held in the years 1928 to 1936 and only in 1932 and 1933 were stripped cars allowed to compete. Surely he remembers Metz being disqualified in 1929 for removing a front mudguard from his Mercedes-Benz ?

I notice that Mr. Jenkinson remarks in “Continental Notes” in the same issue that the Interserie Porsche has a cylinder bore of 90 mm., which he refers to as “that well-known cylinder dimension that engine designers have arrived at since the early days of the internal combustion engine”. I am wondering to which engines D.S.J. refers ? The great racing engines of the early days had bores far larger than 90 mm. and I cannot think of any subsequent successful Grand Prix cars which had 90-bore engines. Could D.S.J. have been thinking of 80-bore engines, which several famous cars used, such as the Coupe de L’Auto Sunbeam, Alfonso Hispano-Suiza and 3-litre Bentley, not to forget the 1951 V12 2-litre Ferrari ?

I remember the Editor recalling the three first-named when he was writing about the first o.h.v. Ford Anglia, which was another 80-bore car.

London, SE. “Old-Timer.”