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 the Spectre engine camshaft, including timing diagram and part numbers.
| Identifier | ExFiles\Box 93\5\ scan0014 | |
| Date | 2nd March 1935 | |
| To RHC.{R. H. Coverley - Production Engineer} x307 FILE ONLY Hs{Lord Ernest Hives - Chair}/Swdl.{Len H. Swindell}7/KW.2.3.35. SpectreCodename for Phantom III. Will you please make the following Camshaft which can be numbered as Hs.{Lord Ernest Hives - Chair}1811. Exhaust cam to lead its inlet cam by 115½° in each case. Exhaust cams to cam forms E.85234. Inlet cams to cam forms E.86370. Otherwise the camshaft is as E.86371 including the extra keyway to Hs.{Lord Ernest Hives - Chair}1768. The timing with .020 clearance should be as follows :- [Diagram] TDC Ex Cl 4° In Op 2° IN Cl 42° Ex Op 54° BDC Hs{Lord Ernest Hives - Chair}/L.H.Swindall. | ||