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 effect of different carburettor needles on acceleration.
| Identifier | ExFiles\Box 13\4\ 04-page018 | |
| Date | 7th July 1928 guessed | |
| ACCELERATION-19-Ex EFFECT OF CARBURETTOR NEEDLE SEMI EXP: CARB: LE C.2972 ACCEL: - FT/SEC² SPEED M.P.H. LEGEND: Solid Line: 90° NEEDLE Dashed Line (x): 85° NEEDLE Dash-Dot Line (o): 95° NEEDLE 12/41 AXLE 18" RIMS (1·07 OF STD) 5·25 C/R SEMI EXP CARB. 114° CAMSHAFT E.82448 TAKEN IN FRANCE BY G.W.H. COMPARATIVE VALUE ONLY. | ||