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).
Experiments for increasing the power output on the 25 HP engine.
| Identifier | ExFiles\Box 5a\5\ 05-page133 | |
| Date | 21th May 1931 | |
| X5771 To RHC.{R. H. Coverley - Production Engineer} From Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}2/KT.21.5.31. EXPERIMENTS FOR INCREASING THE POWER OUTPUT ON THE 25 HP. X5771 We have now instructed the following series of experiments with regard to increasing the power output on the 25 HP. We are anxious to clear up these experiments because W.W. are engaged in re-designing the Japan engine to get more power, and we believe that we can get all the power we want without any re-design. We should be obliged if you would make sure that we get the various pieces instructed as soon as possible so that we can complete these series of experiments. (1) High Lift Rockers (.050 increase) HY{Tom Haldenby - Plant Engineer}/C36/EH14.5.31. (2) 36 D.U.P. Twin induction pipe for carb. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}1/KT.16.5.31. (3) Air silencer for twin Zenith carbs. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}3/KT.20.5.31. (4) Induction pipe for two separate Zenith carb-uretters. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}1/KT.20.5.31. (5) Camshafts with F.{Mr Friese} engine cam forms. Tappet follower to suit. It will be noted that the new rockers to give increased valve lift were instructed in aluminium bronze so that they would not need to be forged. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||