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).
Letter from Rolls-Royce of America discussing carburetter performance issues and potential improvements on Phantom and Silver Ghost cars.
| Identifier | ExFiles\Box 122\1\ scan0022 | |
| Date | 20th September 1927 | |
| ROLLS-ROYCE OF AMERICA, INC. SPRINGFIELD, MASS. X4660 Oy19-E-92027 September 20, 1927 Mr. E.{Mr Elliott - Chief Engineer} W. Hives, Rolls-Royce Ltd., Derby, England. Dear Mr. Hives: Re Carburetter. Whilst in England it was proposed that we might carry out some rough tests on car performance etc. by fitting a Stromberg carburetter to a Phantom car. On further consideration of the fact that we have only one "experimental car" and it is necessary to make it as closely as possible the equivalent of the production chassis, it seems to me that we cannot do this as our means of testing is not elaborate enough to get any essential results. We want to emphasize, however, that besides the effect on the performance of the car, the fact that we use an extra air valve carburetter is probably the most fruitful cause of small annoyances to the owner of the car. The effect of dust, cold weather, and a low grade fuel on the action of an air valve carburetter is such that one can notice a distinct variation in performance from day to day. The tendency of the air valve to stick up causes lean mixture in idling and popping in the exhaust. Further, the low speed acceleration of all of our cars, Phantom and Silver Ghost, is sluggish compared with most American cars because of the tendency of the mixture to go lean at the moment of opening the throttle. We are just attempting to find whether, with our fuel, a slight change in the shape of the air slots will give improved results. We do find that pulling out the air valve spring about 1/16 longer than standard | ||