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).
Performance comparison graph for two different Bentley cylinder heads.
| Identifier | ExFiles\Box 86\1\ scan0129 | |
| Date | 18th February 1935 | |
| COMPARISON OF CYLINDER HEADS (BENTLEY) B.V 74 B2 UNIT SPECIFICATION RHC{R. H. Coverley - Production Engineer}/CP 7/EP{G. Eric Platford - Chief Quality Engineer} 80 11 33 ① CYLINDER HEAD E.B 2050 ② CYLINDER HEAD L.E C 3662 ALL OTHER PARTICULARS, SEE CURVE B.V 73 B.M.E.P. AVOIDING DETONATION (TEST BED EXHAUST SYSTEM) MINIMUM ADVANCE FOR MAXIMUM POWER MAXIMUM ADVANCE AVOIDING DETONATION B.M.E.P (LB/SQ") R.M. 18.2.35 | ||