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 graph of a Marmon engine from a bench test plotting various metrics against RPM.
| Identifier | WestWitteringFiles\J\March1923\ Scan20 | |
| Date | 6th March 1923 | |
| PARTICULARS OF MARMON ENGINE TAKEN IN BENCH TEST REVS. PER MIN. B.H.P. LBS/SQ.IN B.M.E.P. MECH EFFCY % PINTS PET/HP/HR. MECHANICAL EFFCY B.H.P. B.M.E.P. PET/HP/HR. QCL 6.3.23 ROLLS-ROYCE, LIMITED PRINT ROOM. | ||