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).
Design alterations and testing possibilities for the Lighter Phantom Engine, focusing on compression ratios and sparking plug placement.
| Identifier | ExFiles\Box 69\4\ scan0032 | |
| Date | 1st April 1926 | |
| To R.{Sir Henry Royce} from E.{Mr Elliott - Chief Engineer} c. to CJ. Hs.{Lord Ernest Hives - Chair} c. to BY.{R.W. Bailey - Chief Engineer} x8770 E3/M1.4.26. RE. LIGHTER PHANTOM ENGINE. X. 8840 X. 8770 Please find herewith blue prints of LeC. 2229 and 2230., shewing the above. The former shews the general arrangement of the engine. The head has been drawn to suit a compression ratio of 4.5 to 1. The sparking plug points are higher up than we should prefer in the combustion space, but taking everything into consideration the position shewn was thought to be best. It would be possible to use two water ways and drop the sparking plug between them on the off-side of the engine, but on the nearside there is not sufficient room to get the water ways wide enough apart to do much good in lowering the plug. The alterations to the valve gear necessitated/by modified head are dealt with on LeC. 2229 as also are the alter-ations to the oil feed for the rockers. We can make up a head and piston to give the effect shewn on LeC. 2230 as an alternative form of combustion chamber with very little trouble, by leaving some metal on the LeC. 2229 castings. This would be a means of testing a higher compression. LeC. 2230 made to the lower compression ratio of 4.5 to 1 would bring the sparking plugs lower down the walls. The originals of these drawings are attached to BY's copy of this memo. E.{Mr Elliott - Chief Engineer} | ||