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).
Letter addressing a complaint of engine roughness, discussing body mounting, frame resonance, and potential chassis fouls.
| Identifier | ExFiles\Box 146\5\ scan0036 | |
| Date | 31th October 1938 | |
| 1245. W/P. Sr. from Rm.{William Robotham - Chief Engineer} Rm{William Robotham - Chief Engineer}4/R.31.10.38. We have had a general talk round your complaint of engine roughness on your car. You will remember I asked you on the telephone whether you had mounted your body solidly. You said you had now changed over to silent block but the car was not acceptable. In spite of what you say we are sure the whole of your trouble lies in the body mounting. We have no soft engine rubbers either for the front or the back, and experiments we have made show that they have not effected any improvement when we did fit temporarily softer rubbers. All the production cars which we have tried with bodies mounted on them have given us the impression that they are smoother than our experimental cars, amongst which, of course, was 27.G., which you have been using for Demonstration purposes in Paris. I understand from Ev.{Ivan Evernden - coachwork} that he has already sent off to you by Air Mail the two Floatex mountings which you have asked for. You will have to work away at the body mounting and find out whether there is any peculiarity about your body, but the Wraith frame is so resonant that you cannot depart from the scheme which we recommend without danger of running into trouble. Even though you have mounted your body on Floatex, you may have got a foul somewhere which will completely negative insulation. We find that considerable clearance has to be allowed, and your natural desire for a low car may have lured you to reduce the car space between the body and the frame to a dangerously small amount. Rm.{William Robotham - Chief Engineer} P.S. We also suggest that you might make a careful examination for any chassis fouls, such as, exhaust pipes fouling the holes in the cross. | ||