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 give increased clearance around inlet valves.
| Identifier | WestWitteringFiles\W\September1931-November1931\ Scan034 | |
| Date | 5th October 1931 | |
| Attached to Hc/Rm{William Robotham - Chief Engineer}2/AD5.10.31 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 | ||