In 1955 a 2½ litre engine capacity limit was introduced for Formula One racing and 2 years later, in 1957 Formula Two with a 1½ litre limit officially started. In 1956, however, some races were run to this new Formula and because few single seat Formula Two cars had by then been produced sports cars of up to 1½ litres were also allowed to compete. One such race was a support event at the British Grand Prix meeting at Silverstone in July of 1956 and below are two cars that took part in that race - photographed by my brother as I didn't attend that meeting.
They're two OSCA MT4s, but other than that I've no information. My brother tells me neither car was listed in the programme and the first car here was in the blue and yellow colours of Sweden, the other Italian red.