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).
Sketch showing modifications to a Japan cylinder head to increase clearance around the inlet valves.
| Identifier | ExFiles\Box 102\1\ scan0042 | |
| Date | 2nd October 1931 guessed | |
| BEFORE MACHINING INLET <- 1.500 DIA .150 1.000 Rd MOD HEAD .350 Rd 1.125 Rd SKETCH SHOWING MODIFICATIONS TO JAPAN CYLINDER HEAD TO GIVE INCREASED CLEARANCE ROUND INLET VALVES | ||