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 graph showing the effect of increasing clearance around the inlet valve on engine performance.
| Identifier | ExFiles\Box 5a\5\ 05-page173 | |
| Date | 1st October 1937 guessed | |
| R.M.47 EFFECT OF INCREASING CLEARANCE ROUND INLET VALVE JAPAN TWIN ZENITH CARBS. OPEN EXHAUST 112° CRANKSHAFT E 55390 14° DIA. INLET VALVES TIMING TOO EARLY FOR MAX. POWER S/R 5.35 VALVE LIFT .344 MIN. CLCE ROUND INLET VALVE .298 MIN. CLCE ROUND INLET VALVE .100 SEE SKETCH AS ABOVE BUT VALVE LIFT .305 B.H.P. B.M.E.P. R.P.M. TDC EV{Ivan Evernden - coachwork} IV 48 65 1.030'' | ||