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).
Blueprint for a 25 HP engine wedge, also known as a valve spring washer, detailing an alteration.
| Identifier | ExFiles\Box 138\1\ scan0026 | |
| Date | 30th April 1932 | |
| Hs{Lord Ernest Hives - Chair} 590 .050 RAD. +2 -2 .430 DIA -1 .445 DIA -1 .230 DIA +1 .375 +5 -5 TAPER 1 IN 6 .031 SAWCUT ROLLS-ROYCE, LTD. PRINT ROOM APR. 30 1932 DERBY. SCALE 4/1 E 50147 ALTERATION REDUCE .445" DIA To .430" DIA. WEDGE (VALVE SPRING WASHER) 25 HP | ||