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).
Carburettor testing on different engine types and a conclusion on design principles.
| Identifier | ExFiles\Box 39\2\ Scan256 | |
| Date | 11th March 1919 | |
| contd, -3- R5/G11.3.19. ----------- Originally, an RR Carburetter with a moving petrol needle was tested on a two-cylinder engine, and therefore was working at a considerable disadvantage. It was, however, extremely good at slow speeds, but was thought by me not to be as practical as a single jet one with an extra air valve. This carburetter might be used for experimental purposes if a very old one can be found in the stores, and be arranged with a diffuser jet with sufficient hot water and tested on a six-cylinder engine, similar to the "Delage". It is highly desirable in this class of carburetter that the draught of air through the carburetter follows the same law throughout, such as happened with a six-cylinder, engine, whether fully open throttle or a closed throttle. Such carburetters cannot be tested on three-cylinder engines and hardly the same with a four-cylinder engine, and it was for this reason that I was so particularly pleased when we found on reconsidering matters that we could run a six-cylinder engine with a single carburetter without serious loss of power at high speeds. In conclusion, one feels that this carburetter question has been so thoroughly worked out and made in every conceivable form that one thinks that a very carefully worked out design using known features should produce perhaps a better carburetter in a given time, than seeking for novel schemes which I have found in my experience have generally had to be abandoned for the best of the known systems. I say this because I fear that a carburetter with a Contd. | ||