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).
Goshawk I dynamometer test results showing road speeds and various revolution readings.
| Identifier | ExFiles\Box 74\4\ scan0163 | |
| Date | 22th February 1921 | |
| X4134 ROAD SPEEDS. 22-2-21 Dyna. drum and road wheel revs. Dynamometer revs. Tachometer revs. Engine revs. | Theoretical revs. | Actual revs. | Theoretical revs. | Actual revs. | Lbs. | HP. | Theoretical road speed. | Theoretical road speed taking into consideration wear of tyres. | Speedometer readings. 500 | 82 | --- | 328 | --- | --- | --- | 11.71 | 11.57 | --- 750 | 123 | --- | 492 | --- | --- | --- | 17.56 | 17.35 | --- 1000 | 164 | 100 | 656 | 400 | 90 | 21.11 | 23.42 | 23.15 | 30 1250 | 205 | 168.7 | 820 | 675 | 88 | 25.8 | 29.27 | 28.93 | 34 1500 | 246 | 262.5 | 984 | 1050 | 84 | 29.55 | 35.12 | 34.72 | 38 1750 | 287 | 367.5 | 1148 | 1470 | 83 | 33.36 | 40.97 | 40.50 | 44 2000 | 328 | 445 | 1312 | 1780 | 77 | 36.15 | 46.82 | 46.36 | 50 2250 | 369 | 455 | 1476 | 1820 | 74 | 39.05 | 52.67 | 52.08 | 51 2500 | 410 | 500 | 1640 | 2000 | 68 | 39.87 | 58.52 | 57.86 | 57 2750 | 451 | 525 | 1804 | 2100 | 57 | 36.76 | 64.37 | 63.64 | 64 3000 | 492 | --- | 1968 | --- | 49 | 34.48 | 70.22 | 69.43 | 75 GOSHAWK 1. DYNAMOMETER TESTS. | ||