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 plotting various performance curves against pressure in LBS per SQ. Inch.
| Identifier | ExFiles\Box 180\M4\M4.2\ img025 | |
| Date | 25th February 1923 guessed | |
| 90 80 70 60 (LBS. PER SQ. INCH) 50 E.P. | ||