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).
Technical memo regarding a new high compression piston design for the Phantom lll.
| Identifier | ExFiles\Box 94\5\ scan0124 | |
| Date | 23th December 1938 | |
| 336 BY/NS{Norman Scott} c. Rm.{William Robotham - Chief Engineer} c. Rm{William Robotham - Chief Engineer}/Swdl{Len H. Swindell} c. HES DA.{Bernard Day - Chassis Design}14/G.23.12.38. File Swdl{Len H. Swindell} PHANTOM 111 - HIGH COMPRESSION PISTON. Please receive herewith :- E.CD.1119 High Compression Piston - Phantom lll. The new piston which is in accordance with request in Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell}15/JR.{Mr James Royce}12.12.38. will give a compression ratio of 7 to 1 when used with a deturbated combustion chamber which is also shown in this design, it being found necessary to remove the lips at the mouth of combustion chamber in order to provide sufficient room for the addition of the projection at the top of the piston; a .030" thick Klingerite gasket is also called for. The shape and conditions of the projection on piston top follow closely those tried on the Bentley lll high compression piston. The reduced width of top land and also the grinding of the top ring lands are altered to agree with the latest practice adopted for Wraith 1ll pistons. New dies are required for this piston, both internal and external. Will you please detail and instruct for the experimental engine shortly to be built. DA.{Bernard Day - Chassis Design} | ||