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).
Improvements and production plans for the Phantom II car, focusing on a new carburetter, engine mounting, and silencers.
| Identifier | ExFiles\Box 19\1\ Scan241 | |
| Date | 23th November 1932 | |
| X7120. X7770. To R.{Sir Henry Royce} From Hs.{Lord Ernest Hives - Chair} c. to Sg.{Arthur F. Sidgreaves - MD} Sor. c. to E.{Mr Elliott - Chief Engineer} Da.{Bernard Day - Chassis Design} c. to Hy.{Tom Haldenby - Plant Engineer} Hdy.{William Hardy} Hs.{Lord Ernest Hives - Chair}6/MJ.23.11.32. PHANTOM 11 CAR. On the Series of Phantom 11 cars which are now being produced (total of 50) the new semi expanding carburetter, five and a quarter to one compression ratio, and high lift camshaft are only fitted to the Continental type cars. As a result of tests which have been carried out on Sg{Arthur F. Sidgreaves - MD}'s. car and 19-EX. it has now been agreed that a further series of Phantom 11 (100 in number) shall all be made with the latest parts, including the new carburetter. We consider that on the latest Phantom car, a model of which is represented by 19-EX., we have made a very big advance over previous 40/50 cars. The actual result to the customer is that the car can be driven up to 70 M.P.H. on third without any vibration, fuss, or boom. It is a fact that with this car one can run along in third speed and never realise it. The reasons for the improvement are:- (1) Balanced crankshaft. (2) Diamond engine mounting. (3) More efficient carburetter. (4) Resonance type of air silencer. (5) Resonance type of exhaust silencer. We have been greatly helped by the information Rm.{William Robotham - Chief Engineer} brought back from his U.S.A. visit and we are in a position now to say that there is no excuse for booms in any type of car. We have got past the stage now where we want to complain that it is the body which is at fault. The effect of the air silencer on the carburetter is an outstanding feature. We get rid of a tremendous amount of noise and can do it without any loss of power. The point one has to get used to is that to arrive at this result it is necessary to have a big capacity in the air silencer. At first appearance this looks unusual, but as it is coming into general use we should soon get used to it. From the above it will be seen that we have in hand for immediate production a definitely improved Phantom 11. Our concern at the moment is what the next improvement shall be. | ||