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).
Engine power output (BHP) test results table with notes on ignition settings.
| Identifier | ExFiles\Box 3\4\ 04-page268 | |
| Date | 5th May 1933 guessed | |
| -2- (a) (b) (c) (d) (e) ENGINE RPM. BHP. BHP. BHP. BHP. BHP. 500 12.25 - - - - 1000 26 - - - - TOP GEAR 1500 40 39.5 39.5 39.5 - 2000 54 54.2 51.1 55 - 2500 65.2 69 60.5 66.6 - 3000 77.5 80.8 72.5 75.2 78 THIRD GEAR. 3250 82 85.2 72.5 80.6 82 3500 87 91.6 77 F.A. 81.8 1/3 ret 84.8 87.3 3750 90.4 96.4 78 F.A. 83.6 1/3 ret 86.6 90.2 SECOND GEAR. 4000 90 93.2 81 F.A. 85.5 1/3 ret 86.3 91 Notes on Above. (a) In this test the ignition advance given by the governor was such that maximum power was given in the fully advanced position up to 1500 R.P.M. above this speed the lever had to be retarded from 1/3 to 2/3 to give maximum power (this was a standard 20/25 HP. ignition governor). (c) Gives power output with ignition lever fully advanced (d) With ignition governor off 19.G.IV. it was necessary to time at 17° B.T.D.C. to obtain full power in advanced position up to 2500 R.P.M., above this speed full power | ||