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).
Graph of required ignition advance curves (maximum and minimum) versus engine speed for the 20 HP engine.
| Identifier | ExFiles\Box 51\5\ Scan245 | |
| Date | 27th September 1924 | |
| X 4384 20.H.P. G {Mr Griffiths - Chief Accountant / Mr Gnapp} /I MAXIMUM MINIMUM ENGINE DEGREES B.D.C. H.D.P. ENGINE SPEED R.P.M. CURVES SHOWING THE IGNITION ADVANCE REQUIRED ON R.R. 20HP. ENGINE. (FIGURES SUPPLIED BY Hs. {Lord Ernest Hives - Chair} ) 3.2.22 THE CURVES DEFINE THE LIMITS OF IGNITION RANGE, AS EXPERIMENTALLY DETERMINED, OVER WHICH MAXIMUM POWER IS PRACTICALLY MAINTAINED AT EACH SPEED. NEW 25537 e {Mr Elliott - Chief Engineer} /c 27/9/24 | ||