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).
Evaluating a semi-expanding carburetter against existing designs.
| Identifier | ExFiles\Box 178\3\ img228 | |
| Date | 15th June 1932 | |
| HS.{Lord Ernest Hives - Chair} ) FROM R.{Sir Henry Royce} E.{Mr Elliott - Chief Engineer} ) C. to SC. WOR.{Arthur Wormald - General Works Manager} BY.{R.W. Bailey - Chief Engineer} ORIGINAL R2/M15.6.32. x 7080. SEMI EXPANDING CARBURETTER. The specimen shewn me on 19-EX. seems to do its duty extremely well, and better than anything we know of in the World, because it seems rather superior to our old carbur-etters in slow running, in snap acceleration, and vastly superior in maximum power. It still leaves one with a feeling of having a RR. engine. It has upheld the advantages (foretold by me) over the SU. They are some half a dozen points which need not be repeated here, but which we think in a high class job justifies the extra cost. For instance, we should not think of fitting a carburetter to our engine which had not throttle edge carburation, or where the slow speed conditions were so variable as in the case of the SU. This end of the scale is in our case quite constant and fixed by the adjustments. There is some small amount of modification yet to be made, which is not at all serious, and we can on RR. car engines dismiss from our minds for a time all other schemes of carburation that we have tried during the past year or two. It might however be worth remembering that the two separate and single carburetters with fixed jets have done remarkably well, especially for moderate speed torque. These have proved to be the only way in which fixed carburetters can be made to function passably. This earlier scheme, which we had produced in accordance with the experiments made with separate combina-tions, might have made it difficult to choose between the two systems, but we think the double carburetter is the more compli-cated, and the more noisy, and perhaps fails to give us maximum power at high speed. R.{Sir Henry Royce} | ||