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 plotting oil and water temperature against miles run under varying speed and ventilation conditions.
| Identifier | ExFiles\Box 19\4\ Scan083 | |
| Date | 2nd July 1930 guessed | |
| GRAPH IV 62 M.P.H. C.O. CLOSED CAR OPENED FULL OUT C.O. OPEN 83 M.P.H. ATS TEMP 20°C OIL TEMP TOP WATER VENTILATED UNDERSHIELD ALL BONNET SHUTTERS OPEN TEMP C° 100° 90° 80° 70° MILES RUN 25 30 35 | ||