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).
Engine's test bench performance, detailing total run time and slow running speeds.
| Identifier | ExFiles\Box 69\4\ scan0270 | |
| Date | 16th December 1924 guessed | |
| 111-EAC-11. This engine has been run a total of 28 hours on the test bench. With the same carb. setting as that used for the power curve, slow running of 160 r.p.m. was obtained on the battery, 210 r.p.m. for the Magneto, - these speeds being maintained indefinitely. | ||