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).
Graph comparing the valve areas of sleeve versus poppet valves for a 3.500 bore engine.
| Identifier | ExFiles\Box 133\2\ scan0159 | |
| Date | 20th June 1935 guessed | |
| VALVE AREAS - 3.500 BORE ENGINE DURATION OF VALVE OPENING 230° ____ SLEEVE VALVE - - - - POPPET VALVES (LEC 3855) IN 1.600 DIA Ex 1.400 DIA VALVE AREA - SQ. INS 2.5 2.0 1.5 1.0 0.5 0 INLET EXHAUST OPENING CLOSING DEGREES ON CRANKSHAFT 0 30 60 90 120 150 180 210 FIG. 1 410S.J | ||