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).
On the preliminary test results for a modified air-silencer carburetter for Phantom II engines.
| Identifier | WestWitteringFiles\U\May1930-July1930\ Scan008 | |
| Date | 7th May 1930 | |
| To R.{Sir Henry Royce} (Held up) From Hs{Lord Ernest Hives - Chair}/CHP. c. to SG.{Arthur F. Sidgreaves - MD} Wor.{Arthur Wormald - General Works Manager} c. to Rg.{Mr Rowledge} Da.{Bernard Day - Chassis Design} c. to E.{Mr Elliott - Chief Engineer} By.{R.W. Bailey - Chief Engineer} MODIFIED AIR SILENCER CARBURETTER (L.E.C. 2736). Preliminary tests have now been carried out on the modified air-silencer carburetter for P.II engines; the results of which shew that we are still losing too much power by the use of this instrument. This carburetter is, however, a big improvement on the original one (L.E.C. 2734), a report on which was circulated 9.12.29. The construction has been modified so that a standard high-speed choke and diaphragm are utilised, also the air-valve is of standard dimensions so far as the air ports etc., are concerned. The only variation from a standard carburetter, is therefore the air-silencer and the cowling around the air-valve ports. The curve V.850 shews that this carburetter causes no loss of power up to 1500 R.P.M.; after which the loss increases to a maximum of 8 B.H.P. (3%) at 2750 R.P.M. (this figure being the excess of loss over that caused by the Std. air-intake). In order to ascertain the loss caused by each individual part of the air-silencer etc., it is necessary to know what loss is occasioned by the standard type air-intake: therefore the top curve on V.851 (Std. carb. with air-intake removed) is taken as the datum. The total loss caused by the air-silencer and air-port cowling is therefore, 10.5 BHP. | ||