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 the cooling performance of a 40/50 model against a Hispano Suiza during a hill climb test.
| Identifier | ExFiles\Box 38\2\ Scan213 | |
| Date | 26th September 1924 | |
| COMPARATIVE COOLING TESTS ROLLS ROYCE 40/50 & HISPANO SUIZA SWINSCOE HILL CLIMB (FULL THROTTLE) AV SPEED 30 MPH RADIATOR TEMPERATURES °C MILES RR 40/50 STANDARD. NO FAN. NO BONNET. HISPANO SUIZA STANDARD. NO FAN. NO BONNET. R.B.Cotton 26/9/24 | ||