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).
Report comparing vehicle performance and acceleration times using Petrol versus Pyrol fuel.
| Identifier | ExFiles\Box 32\1\ Scan073 | |
| Date | 11th May 1923 guessed | |
| min, speed, speed at finish (danger post right hand side) Time Taken. Three tests were taken two with passengers one without. The average tests came out as follows. | | Petrol | Pyrol | | :--- | :--- | :--- | | Speed at start | 5 MPH | 5 MPH | | " on 2nd corner | 21 | 20 | | " at finish | 31 | 28 | | Max speed attained | 32 | 31 | | Time | 1 min 18.2 sec. | 1 min 20.1 sec. | Acceleration on top gear, tests carried out on London Rd. straight Shardlow end. On these tests the engine at low speeds hesitated due we look it to the heavy spirit not being carried up by the velocity of the air, also it was noticed that on buffing up on these tests, wet Pyrol came out of the throttle very bad. and the exhaust was very obnoxious. The results of these tests were | | Petrol | Pyrol | | :--- | :--- | :--- | | 10 - 20MPH | 5.935 sec | 7.00 sec | | 20 - 30 | 5.935 " | 6.82 " | | 30 - 40 | 7.6 " | 8.50 " | | 40 - 50 | 12.250 " | 19.45 " | Average time London Rd both ways. | ||