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).
Table outlining the atmospheric temperatures at which car engines will boil with different radiator systems and cooling configurations.
| Identifier | ExFiles\Box 24\4\ Scan281 | |
| Date | 21th November 1924 guessed | |
| -4- As a clear means of indicating the respective conditions of cooling existing in the R.R. standard matrix, large matrix and Hispano system, we give below a table of atmospheric temperatures above which the cars will inevitably boil if driven for sufficiently long on full throttle at 30 m.p.h. under the cooling conditions indicated. This figure is obtained as follows. The difference between the top and bottom radiator temps. of all three systems at 90° is approx. 10°C. If therefore the mean radiator temp. exceeds 95°C, the top water will be boiling. Hence the atmospheric temp. at which the car will overheat = 95 - where is in C°. | Condition of car. | | Ats. temp. above which boiling may occur. | | | |--------------------|-------------|-------------------------------------------|---------------|------------| | | | 20 1/4" matrix. | 23 3/4" matrix. | Hispano | | Standard | 30 m.p.h. | 18°C | 25°C | | | Shutters (4) | " " | 24.3°C | 30°C | | | Louvres. | " " | 25.9°C | 31°C | 34.35°C | | Shutters (8) | " " | | 32°C | | | Bonnet side off. | " " | 32.55°C | 39°C | | | Louvres. | 20 m.p.h. | | 25°C + | 33.65°C | | | | | + Possibly lower than this - figure requires confirming. | | contd :- | ||