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).
Test report detailing the effect of various car alterations on top water temperature.
| Identifier | WestWitteringFiles\U\August1930-November1930\ Scan021 | |
| Date | 28th February 1921 guessed | |
| VALUE OF VARIOUS ALTERATIONS TO CAR CONDITION. 75 M.P.H. Alterations in top water temperature from standard un-ventilated condition. C.C. opened. | 3°C. drop Radiator shutters removed. | No difference. Head and spot lamps removed. | 2°C. drop. Ignition retarded 3 degrees on flywheel. | 2°C. rise Fan removed. | 5°C. rise All out at M.P.H. Fan removed. | 8°C. rise Gear ratio reduced 87 | 1°C. rise | ||