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 Mean Effective Pressure (MEP) against RPM for different ramp head and piston configurations at maximum power.
| Identifier | ExFiles\Box 134\1\ scan0119 | |
| Date | 23th December 1938 guessed | |
| CURVE b. RAMP HEAD COMPARISONS. (MAX. POWER) ① RAMP HEAD. STD. PISTON. 6.6 : 1 RATIO ② " " CROWN PISTON. 6.6 : 1 " ③ " " " " 7.3 : 1 " PLUG IN EXHAUST POSITION. Nº ③ RECOMMENDED BY TAUB. VALVE TIMING. I.O. 10º BTDC E.O. 55º B. I.C. 37º PB E.C. 3º P. M.E.P. R.P.M. | ||