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).
Valve timing and the induction system for the Aluminium Phantom Engine.
| Identifier | ExFiles\Box 66\2\ scan0259 | |
| Date | 10th September 1926 | |
| To Hs.{Lord Ernest Hives - Chair} from R.{Sir Henry Royce} X8230 RL/M9.10.26. RE. ALUMINIUM PHANTOM ENGINE. X. 8770 X8070 X. 8840 X. 8080 (struck through) X. 8230 X. 8060 Regarding the power of the Phantom engine we want to hold open the inlet valves longer than on the aero engines because we do not require high compression at slow speed on account of detonations, and we do want the cyls. to fill up at high speed, so that we should naturally be holding the valves open at least 50° above bottom dead centre. The next point is, does overlap worry us: possibly we could do with an overlap of 20°. We do not think an early exhaust opening is particularly good, and suggest 45° before dead centre. It is assumed that the above mentioned figures occur when the valve is open .010". As regards the induction system, our next step experimentally should be to try the slotted induction pipe on this engine. R.{Sir Henry Royce} | ||