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).
Effect of various car alterations on top water temperature at different speeds.
| Identifier | ExFiles\Box 29\3\ Scan271 | |
| Date | 1st September 1930 guessed | |
| VALUE OF VARIOUS ALTERATIONS TO CAR CONDITION. 75 M.P.H. Alterations in top water temperature from standard un-ventilated condition. C.O. opened. 3°C. drop Radiator shutters removed. No difference. Head and spot lamps removed. 2°C. drop. Ignition retarded 9 degrees on flywheel. 2°C. rise Fan removed. 5°C. rise All out 80 M.P.H. Fan removed. 8°C. rise Gear ratio reduced 6% 1°C. rise | ||