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 Brake Horse Power and Brake Mean Effective Pressure for large vs small valves under different carburetor configurations.
| Identifier | Morton\M19\ img236 | |
| Date | 20th August 1931 | |
| COMPARISON OF LARGE & SMALL VALVES RM.{William Robotham - Chief Engineer} P.15 4.78 CR{Mr Cra???ster / Mr Chichester} W.W. 114° SHAFT L.E.C. 2818 OPEN EXHAUST INS. DEPN. 3000 RPM LARGE VALVES C DENOTES CLAUDEL 1.90 T TWIN CARB 1.4 DIA CHOKE 2.55 B.H.P. B.M.E.P. LBS/SQ" Valve Timing Diagram: Ex Inl 10 52 76 8 T.O.13. C.E. Key: ① INLET VALVE THROAT 2.00 TREPANNED ROUND PORTS ② INLET VALVE THROAT 1.680 30° SEAT Hs.{Lord Ernest Hives - Chair}372 Curve Labels: ①C ②C ①T ②T R.P.M Axes Values: BHP: 90, 100, 110, 120, 130, 140, 150, 160, 170 BMEP: 70, 80, 90, 100, 110, 120 RPM: 500, 1000, 1500, 2000, 2500, 3000, 3500 Date: 20/8/31 | ||