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).
Summary of radiator tests showing critical atmospheric temperatures under various conditions.
| Identifier | WestWitteringFiles\W\May1931-August1931\ Scan087 | |
| Date | 4th September 1931 | |
| SUMMARY OF RADIATOR TESTS. 25-EX. 4.9/1 C/R.{Sir Henry Royce} 1931. NO BONNET VENTILATION. Level road. | | Critical ats. temp. C° | | | | Small tube rad. .312 across flats. | Large tube rad. .360 across flats. | | 60 M.P.H. | 42°C. | 40.5°C. | | 70 M.P.H. | 39.5°C. | 35.0°C. | BONNET VENTILATION 3 SHUTTERS/SIDE. Level road. | | critical ats. temp. C° | | | | small tubes. | Large tubes. | | 60 M.P.H. | 46°C. | 44°C. | | 70 M.P.H. | 42°C. | 38.5°C. | BONNET VENTILATION 3 SHUTTERS/SIDE. Hill climbing. | | critical temperature. | | Large tube radiator. | 26°C. | | Small " " | 30°C. | | ||