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 and analysis of engine performance, showing Mean Effective Pressure vs. R.P.M.
| Identifier | ExFiles\Box 134\2\ scan0191 | |
| Date | 1st February 1939 | |
| -4- ③ As CURVE ① BUT STD PISTONS -.030 BELOW CYLINDER BLOCK 6.25:1 COMP RATIO --- MAX POWER x---x NON DETONATING Graph Data: X-Axis: R.P.M. (1000, 2000, 3000) Left Y-Axis: MEP lbs/□' (100, 110, 120, 130) Right Y-Axis: IGN. ADV. °BTDC (20, 40) Curve (3) with the cylinder head as designed but incorporating the increased transfer throat area FD.{Frank Dodd - Bodies}292 - 1.75 sq.in. - 6.25 : 1 C.R. a maximum MEP of 126 lbs/sq.in. is developed at 2000 r.p.m. and from 1000 r.p.m upwards the engine is clear of detonation at full throttle. At 3000 r.p.m it will be seen that it is necessary to over advance by approx. 15° to bring in detonations. Below 1000 r.p.m. the engine detonates on full power and at 750 r.p.m. the power has to be dropped by approx. 4 lbs/sq.in. by retarding to be clear of detonation. Continued. | ||