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).
Test results for car 49-GB at Brooklands, including lap times, speedometer accuracy, and acceleration.
| Identifier | ExFiles\Box 29\3\ Scan077 | |
| Date | 3rd June 1920 | |
| TESTS CARRIED OUT AT BROOKLANDS WITH 49-GB CAR. 3.6.20 Test 12. Condition. - Hood down - screen down - cut-out closed. open Lap 1. Time. 2 m.18 1/2 sec. Speedometer, min. max. at stop. Lap 2. Time. 2 m.18 sec. Speedometer, min. max. at stop. Lap 3. Time. 2 m.17 sec. Speedometer, min. max. at stop. 1/4 mile flying. Time. 24 1/2 secs. Speedometer. at stop. 1/4 mile from 10 M.P.H. Time. 40 secs. Speedometer. at stop. Speedometer tests. 1.6.20. Spmter. Readings. | Distance. | Time in secs. 30 M.P.H. | 1/4 mile | 62 45 " | 1/4 " | 44 60 " | 1/4 " | 35 Acceleration Tests. Hood up - screen up - cutout closed No Wind. Speed. | Time taken in secs. 10 to 20 M.P.H. | 4 10 to 30 " | 7.5 10 to 40 " | 12 10 to 50 " | 18 10 to 60 " | 24 1/4 mile from 10 M.P.H. 40.6 secs. Acceleration Tests. 2-6-20. Hood up and screen up - cutout open. Speeds. | Time in secs. 10 to 20 M.P.H. | 3 10 to 30 " | 7 10 to 40 " | 11 10 to 50 " | 15 - 10 to 60 M.P.H. 21 secs. | ||