Drawings for the 'Spectre' engine's cylinder head, gasket, and block, confirming a 6 to 1 compression ratio for the first build.
| Identifier | ExFiles\Box 93\4\ scan0002 | |
| Date | 18th January 1934 | |
| To BY. {R.W. Bailey - Chief Engineer} from E {Mr Elliott - Chief Engineer} /JNR. {Charles L. Jenner} c. Hon. Hs. {Lord Ernest Hives - Chair} E {Mr Elliott - Chief Engineer} /JNR. {Charles L. Jenner} 1/HP.18.1.34. re 'Spectre(Codename for Phantom III)'. Please receive herewith - LeC.3754 showing further views of the cylinder head, the gasket, and the upper part of the cylinder block. Also herewith - LeC.3764 showing a cross section of the cylinder head arranged for a compression ratio of 6 to 1. It has been decided to build the first engine with this ratio. E {Mr Elliott - Chief Engineer} /JNR. {Charles L. Jenner} Handwritten: X4444 319 | ||
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).