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).
Needle valve seat and fuel flow tests with recommendations for improvement.
| Identifier | ExFiles\Box 13\3\ 03-page136 | |
| Date | 7th November 1929 | |
| HS{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}2/AV/7.11.29 contd. -3- of the needle valve seat because we get no improvement when we open up dia x. from .218 to .312. We also tried under-cutting the seat to reduce the length of the narrow bore (Hs.{Lord Ernest Hives - Chair} 241) but this produced no appreciable improvement either. We have made these tests because, though we can run all out on Brooklands without trouble, our margin is so small that any dirt in the filter causes starvation. Therefore the filter has to be cleared more frequently than is desirable. Also because as we increase our engine power we shall require more fuel. We are not in a good position at present for full throttle hill climbing. Recommendations. (1) That we do away with the banjo union carburetter connection and refrain from using these connections where optimum flow is required. (2) That we improve the flow through the needle valve seat. We are carrying out tests to find the best way of doing this without increasing the tendency to flood. Further tests we have carried out indicate that we shall not get very much improvement until the needle valve seat restriction is reduced. We have opened out the filter head passages and unions as far as possible and get the following results. | ||