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).
Engine test results comparing performance with standard, flight-tested, and long-duration camshafts.
| Identifier | ExFiles\Box 43\3\ Scan194 | |
| Date | 17th September 1928 | |
| contd :- -2- (2) The engine was sent back to the Works and a further test was conducted with air boxes (17.9.28). The results are shewn on Sheets 1. and 2. dotted line. There appears to be a gain in B.HP. compared with the original tests. Unfortunately, the engine was not tested as delivered from the aircraft, as due to a misunderstanding, the camshaft was stripped but afterwards put back and re-timed. The increase in power between tests 1. and 2. may be partly due to the engine having run itself in during the flight time with a possible benefit from a slightly changed timing. (3) Modified camshafts fitted and tests conducted with exhaust gases collected but exit pipe open to atmosphere. A whole range of test figures were obtained at full throttle with the air box pressure varying from ground level conditions to those at 15,000 ft. TABLE OF COMPARISONS. Full throttle 10,000 ft. TEST. Air boxes Inlet temp: +15°C. Corrected for alt:conditions. Air temp.-5°C. Engine throttled under ground level conditions. 2250 | 2500 | 2250 | 2500 | 2250 | 2500 (1) Original standard cams. | 435 | 485 | 473 | 529 | 437 | 462 (2) After flight tests. | 442 | 493 | 481 | 538 | 455 | 485 (3) Long duration cams. | 460 | 515 | 500 | 562 | 476 | 512 With the long duration cams, the ground level power at full throttle, 29.9" Hg. Barometer, 15°C. temp., is 730 B.HP. at 2250 } 100% Benzol. 820 B.HP. at 2500 } | ||