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).
Development and comparative performance of single versus dual carburetter setups for the Continental Phantom and 25 HP models.
Identifier | ExFiles\Box 19\1\ Scan186 | |
Date | 2nd March 1932 | |
87120. Sg.{Arthur F. Sidgreaves - MD}1/WT2.3.32. S/W. -> E...From Sg.{Arthur F. Sidgreaves - MD} Copy to Hs.{Lord Ernest Hives - Chair} Wor.{Arthur Wormald - General Works Manager} Continental Phantom and 25 H.P. You will have received my Sg.{Arthur F. Sidgreaves - MD}10/E2.3.32 indicating why we do not feel justified in persevering further at the present time with improved "Phantom II" Continental performance with the use of two S.U. carburetters. Alternatively you are urging forward with all speed and all haste the development of the new R.R. "Phantom II" carburetter with a view to obtaining as near as possible a similar performance to that obtained with 27-EX at the present moment. We understand from Hs.{Lord Ernest Hives - Chair} that even when the R.R. new carburetter is knocked into shape it is not likely to give any performance nearer than 90% of that of the S.U. carburetter, one of the chief reasons being that only one carburetter will be in operation instead of two. R.{Sir Henry Royce} points out in R.1/M26.2.32 that we should give the same treatment to the Phantom as we did in the case of J.1 where the B.M.E.P. at 1,500 revs was extremely encouraging. PN.{Mr Northey} understands from Hs.{Lord Ernest Hives - Chair} that the R.R. Phantom carburetter now being tested would not be suitable, as it stands for working as a pair as in the case of 27-EX, but that some further design would be called for enabling two carburetters to be fitted and tested, probably located in a downdraft position. I do not of course know how much work will be involved, or length of time occupied before there could be running experimentally two of the improved R.R. carburetters as suggested, and I should like to have some information on this point as early as possible. Also, I should like to have an indication as to what would be the additional cost to us of running two of such carburetters in production instead of one. It would appear, in any case, the amount of improvement in performance, whatever we do with the present standard Continental chassis, is only a question of a few percent here and there, and we ought to leave no line unexplored which might add another one or two percent in the right direction. I certainly feel that unless some good reason can be shown for avoiding two carburetters, | ||