Piers Courage
At Silverstone both of the works P83s suffered suspension failures in practice, and as a result Stewart took over the Reg Parnell P83 of Irwin, who in turn was given the P261 of Piers Courage, who had to sit out the race. For once Spence out-qualified Stewart with the two cars in 11th and 12th place but at the end of the second lap Spence's electrics caught fire and he lost ten minutes while the car was repaired. Stewart broke down after 20 laps with transmission problems and after 44 laps Spence retired from 13th with further electrical problems.