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 showing the required ignition advance range against engine speed for a 20 HP engine.
| Identifier | ExFiles\Box 54\5\ Scan282 | |
| Date | 3rd February 1922 | |
| [ "20.HP", "MAXIMUM", "MINIMUM", "ENGINE DEGREES B.D.P.", "ENGINE SPEED R.P.M.", "CURVES SHOWING THE IGNITION ADVANCE REQUIRED ON R.R. 20HP. ENGINE.", "(FIGURES SUPPLIED BY Hn. {F. C. Honeyman - Retail orders} ) 3.2.22", "THE CURVES DEFINE THE LIMITS OF IGNITION RANGE, AS EXPERIMENTALLY DETERMINED, OVER WHICH MAXIMUM POWER IS PRACTICALLY MAINTAINED AT EACH SPEED.", "R.R.P.", "REF. JUDGE", "T/THG" ], | ||