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).
Drawing of a 3 1/2 Litre S.S. Inlet Valve and associated components.
| Identifier | ExFiles\Box 126\5\ scan0146 | |
| Date | 8th March 1938 guessed | |
| 3 1/2 LITRE. S.S. VALVE-INLET., S.S.20, 45/64", .0468, 1/32", 23SWG(.024), 31/32", 5/8", 5/16", 11/32", .400, 7/16", 1 1/64", 9/16", 23/64", 29/32", 5 23/32", FACE ANGLE 30°, INLET, 1 17/32", 1"R, 27/64"R, 3/64", .309, .258, 15/64", 11/32, 15/64", 15/32", 7/64", 1/16", 13/32", .046, 27/64" | ||