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).
Selection of new valve springs, weighing the benefits of different specifications against potential engine modifications.
| Identifier | ExFiles\Box 43\3\ Scan124 | |
| Date | 1st January 1927 | |
| To E.{Mr Elliott - Chief Engineer} RG.{Mr Rowledge} BY.{R.W. Bailey - Chief Engineer} Hs.{Lord Ernest Hives - Chair} From R.{Sir Henry Royce} c. to BJ. Wor.{Arthur Wormald - General Works Manager} [Handwritten]: X4003 [Stamped, inverted text]: CERTIFICATE [Stamped, inverted text]: ...ROYCE ENGINES...R1/M20.1.27. F.10. VALVE ROCKERS, SPRINGS ETC. X.4003 X.3822 Referring to E's memo. if we can get some results from the springs with the new characteristics we could judge whether 1.3 or 1.4 springs were required. I have been hoping to hear that these new springs (with low max: stress and big stress range) are a decided advance in reliability, the valves following the cams safely up to the maximum speed, and less liable to surge and break. One feels we ought to be thorough with the move doing all that is necessary to get a good clearance (your Sch.l.) so that with extra cutting we can get 1.4 springs in, but I think we ought to avoid increasing the engine width by the .8 suggested, and avoid altering the cyl. block even if we have to be content with the 1.3 spring. I must therefore leave it with E.{Mr Elliott - Chief Engineer} to decide whether (1) or (2), with the latest information from Derby about the springs. Apparently if we avoid the rockers leaving the cams, and the surging, we shall not get broken springs, especially with the low max: stress. The high rating springs seems to meet the requirements of the present cams, and are definitely in the opposite contd | ||