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).
Slow running performance improvements using camshaft Hs.1536 with Cadillac tappets, detailing timing specifications.
| Identifier | ExFiles\Box 124\3\ scan0263 | |
| Date | 5th December 1934 | |
| X 3317 To E.{Mr Elliott - Chief Engineer} from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} c.c. to Wor.{Arthur Wormald - General Works Manager} c.c. to By.{R.W. Bailey - Chief Engineer} Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}2/KW.5.12.34. Further to our report on slow running. The engine on the test bed with the camshaft Hs.{Lord Ernest Hives - Chair}1536 running with Cadillac tappets shows a marked improvement in slow running. The timing at .020 tappet clearance is as follows :- I.O. 7º P.T.D.C. E.O. T.D.C. I.C. 53º P.B.D.C. E.C. 48º B.B.D.C. This camshaft was the best we could do with the original SpectreCodename for Phantom III cam forms. It is always difficult to get a true impression of slow running on the test bed, and therefore we cannot yet say that we are good enough. It appears that Lec. 4120 should cover our requirements, as far as cam forms are concerned. HS{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||