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).
Power and B.M.E.P. performance graph for a 4 1/4 Litre Bentley engine.
| Identifier | ExFiles\Box 99\1\ scan0016 | |
| Date | 10th May 1938 guessed | |
| 4 1/4 LITRE BENTLEY POWER S 40 COMP. RATIO 6.3 (EW. 1296) B III IND N - SYSTEM (2 H4 SU CARBS) ⓐ NO RESTN. ⓑ 500 RESTN. ⓒ 375 RESTN. B.H.P. B.M.E.P. R P M | ||