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).
Comparison of Phantom II acceleration times for three different experimental car configurations.
| Identifier | ExFiles\Box 92\2\ scan0164 | |
| Date | 8th August 1933 | |
| x7771. 8.8.33. P.II. ACCELERATIONS (underlined) 25-EX. 5-1 c/r.{Sir Henry Royce} old type camshaft, 11x41 axle. old type carburetter. Complete car wt. 48 3/4 cwt. 19-EX. 5 1/4-1 c/r.{Sir Henry Royce} new type 114° camshaft. 12x41 axle. Semi expanding carburetter. Car wt. 49 1/4 cwt. 27-EX. 28 1/2 cwt. 11 x 41 axle. 5 1/4 c/r.{Sir Henry Royce} 114° camshaft. Semi expanding carb. | SPEEDS. | MEAN WAY ACCELERATIONS. | | | 19-EX | 25-EX | 27-EX | |---------|-------|-------|-------| | 10-20 | 5.1 | 4.1 | 3.8 | | 20-30 | 4.9 | 4.3 | | | 30-40 | 4.8 | 4.5 | 10.8 | | 40-50 | 6.0 | 5.7 | | | 50-60 | 7.3 | 6.4 | 17.2 | | 60-70 | 10.4 | 8.6 | | Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||