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).
Requesting a cylinder head with a 7½:1 compression ratio and flat top pistons for a High Power engine test.
| Identifier | ExFiles\Box 134\2\ scan0180 | |
| Date | 5th October 1938 | |
| 1129a? To Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell}from Rm.{William Robotham - Chief Engineer} Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell}3/MH.{M. Huckerby}5.10.38. In order to get a range of parts to test on the High Power engine we should like you to put through a cylinder head with 7½ : 1 compression ratio with flat top pistons. Rm.{William Robotham - Chief Engineer} | ||