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 constant speed petrol consumption for various induction systems and car models.
| Identifier | ExFiles\Box 122\4\ scan0224 | |
| Date | 25th March 1939 guessed | |
| CONSTANT SPEED PETROL CONSUMPTION MILES/GALLON CONSTANT SPEED M.P.H. B III S.U. INDUCTION SYSTEM - B.S.A. NEEDLES. STANDARD WRAITH SYSTEM B III SYSTEM Z NEEDLES 4 1/4 BENTLEY II Y-Axis (Miles/Gallon): 10, 12, 14, 16, 18, 20, 22, 24 X-Axis (Constant Speed M.P.H.): 20, 30, 40, 50, 60, 70 | ||