From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Graph of overheating test results for a Phantom II Cabriolet with various bonnet and undershield configurations.
| Identifier | ExFiles\Box 64\1\ scan0074 | |
| Date | 25th June 1931 guessed | |
| GRAPH II STANDARD P.II CABRIOLET 19 E.X. Axle Ratio 14 x 52 Wt. 48 Cwt. EMPTY. TEMP. AT WHICH CAR WILL OVER-HEAT EVENTUALLY. (100°C - TOP WATER TEMP) STANDARD No VENTILATION 35°C REAR BONNET SHUTTERS OPEN ONLY 37°C FRONT UNDERSHIELD OFF 38°C FRONT BONNET SHUTTERS OPEN ONLY 38.5°C FRONT AND REAR BONNET SHUTTERS OPEN 41°C LOUVRED BONNET. 41.5°C LOUVRED BONNET. VENTILATED FRONT UNDERSHIELD 43.5°C FOR THIS TEST CAR DRIVEN AT A STEADY 60 M.P.H. ROUND BROOKLANDS TRACK. C.O. CLOSED. DURING TESTS ATS TEMP AVERAGED ABOUT 21°C. VARYING FROM 17°C TO 24°C. (COMPENSATED FOR ON EACH TEST) COMPARISON OF VARIOUS ALTERATIONS TO CAR. Standard Rad. 6 m/m 7 1/2 m/m Tubes 4.00" DEEP. FRONTAL AREA. | ||