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 comparing stabilised engine water temperature against car speed for bonnets with vertical and horizontal louvres.
| Identifier | ExFiles\Box 16\2\ Scan003 | |
| Date | 24th July 1930 guessed | |
| FILE UNDER PII RAD x/7/50 ENGINE COOLING. P.I. COMPARISON BETWEEN STANDARD VERTICAL LOUVRED BONNET AND BONNET TO WITH HORIZONTAL LOUVRES. RADIATOR WITH 6x7 1/2mm TUBES WITH INDENTATIONS. CAR 19EX, OTHERWISE STD. STABILISED RUNNING TEMPERATURE AT 20°C AIR TEMP. STABILISED WATER TEMP °C CAR SPEED M.P.H HORIZONTAL LOUVRES VERTICAL LOUVRES TOP WATER TEMP. MEAN WATER TEMP. | ||