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 comparing ignition advance required for maximum power on E.A.C. and Hispano engines, showing the effect of synchronised dual ignition.
| Identifier | ExFiles\Box 22\1\ Scan146 | |
| Date | 10th March 1924 guessed | |
| IGNITION ADV. REQUIRED TO OBTAIN MAX. POWER ON E.A.C. & HISPANO, SHOWING EFFECT OF THE SYNCHRONISED DUAL IGNITION ON HISPANO. E.A.C. GIVES AUDIBLE DETONATION TO APPROX. 1300 RPM. HISPANO GIVES AUDIBLE DETONATION TO 1000 RPM WHEN USING ONE IGNITION ONLY. WITH THE TWO IGNS. ON HISPANO THERE IS NO AUDIBLE DETONATION. Y-AXIS: FIRING POSN DEGREES BEFORE TOP CENTRE. X-AXIS: ENG. R.P.M. GRAPH LINES: E.A.C. HISPANO 1 PLUG HISPANO 2 PLUGS ADOPTED CURVE | ||