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).
Specifications for machining a Large Bore Bentley engine head to achieve a 6.4/1 compression ratio.
| Identifier | ExFiles\Box 82\4\ scan0186 | |
| Date | 14th November 1935 | |
| To By.{R.W. Bailey - Chief Engineer} XOD Hs{Lord Ernest Hives - Chair}/Smth.24/KW.14.11.35. Large Bore Bentley. When the head Ex.18392 is machined to give 6.4/1 C.R. (119 c.c. capacity), the depth of the combustion chamber from the ceiling to the joint face is 1.150". We have obtained this figure by direct measurement. This is using a .050" gasket and with the crown of the piston .030" from the top face of the block at T.D.C. Hs{Lord Ernest Hives - Chair}/Smth. | ||