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).
Measurements on a six-cylinder engine regarding crank flexibility, compression ratios, and harmonic amplitude.
| Identifier | ExFiles\Box 140\3\ scan0134 | |
| Date | 1st January 1938 | |
| Actual measurements carried out on a six cylinder engine with a very flexible crank ten years ago. As compression ratios are raised, amplitude of harmonic B. which is the period we believe you experience at 1950 R.P.M., increases until there is a danger of the shaft breaking. -------------- | ||