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).
Summary of road tests on different engine induction and manifold systems for the Phantom model.
| Identifier | WestWitteringFiles\R\2December1927-February1928\ Scan183 | |
| Date | 8th February 1928 guessed | |
| contd :- -3- Most of the road tests have been made with the usual exhaust hot spot but without the butterfly baffle in the down pipe and we have found that smooth operation of the engine can be obtained almost as soon after starting from cold as when using the standard induction system with the exhaust butterfly baffle. It would appear from our general impression on the road that this system, due to its better cold distribution, would allow us to get rid of the objectionable butterfly exhaust baffle but we are making more definite tests in this direction to see if deleting the butterfly is permissible. As we stated before the single piece manifold gave better results than the built up type. We are however preparing a built up or two-piece manifold - with the same internal contours as the former so that the interior of this can be more accurately finished and should give more consistent results. The two piece pipe manifold was tested with a ver- tical RRCH. carburetter and gave particularly good distribution. General we may say that the weir type manifold is the most promising system in conjunction with the standard carb. we have tested on the Phantom. When tested as a model for the EAC.10 the results were quite satisfactory and there is every evidence to shew that when modified - i.e. carb. lowered - for the EAC.14 it should be superior to the standard system. We shall later be able to see how it compares with the short underfed induction pipe. A detailed report with curves of these tests follow. Hs{Lord Ernest Hives - Chair}/A.C.Lovesey/ | ||