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).
Power test report comparing a Vulture engine unit against a Phantom II, detailing differences in construction and performance.
| Identifier | ExFiles\Box 123\3\ scan0102 | |
| Date | 17th January 1934 | |
| -3- Hs{Lord Ernest Hives - Chair}/Bwd1.1/KW17.1.34. --------------------- that a lighter mesh pinion would cure this; otherwise there is no rattle whatever from the remaining gears down to slow running speed. Power Test. ----------- The unit gives an appreciable power increase over an 8.1 litre (same capacity) Ph.II at the peak power speeds. From the curve the greatest increase is at 3000 r.p.m. showing 16 B.H.P. or 8.5%, and other than the conditions given below the units compared were run under similar conditions. (1) Vulture unit has dry liners in aluminium cylinder blocks, against Phantom cast-iron blocks. (2) Vulture has no gearbox to drive through when mounted on the test bed. (3) Slight difference in cam shafts. Vulture having silent tappets and no clearance runs with a little longer duration cam; has modification to cam contour to suit roller follower and was run with the timing approximately 1/2 tooth later. Below 1500 r.p.m. the units develop almost identical power, the comparative curves being shown on Hs.{Lord Ernest Hives - Chair}1271. Hs{Lord Ernest Hives - Chair}/L.H.Swindall. | ||