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).
Prop-shaft vibration and exhaust boom issues found in completed Phantom III cars.
| Identifier | ExFiles\Box 91\1\ scan0406 | |
| Date | 18th August 1936 | |
| X300 GRY{Shadwell Grylls} WYMAN Whyman noted Lown LA{L. A. Archer}16/T18.8.36 PHANTOM III COMPLETE CARS We have now completed 10 of the above cars and most of them are now in service. Generally the cars are coming out quite well and giving satisfaction, especially in the case of Lord Portarlington. He has now made two trips abroad with the car, and except for the broken valve springs the car has run very well, and he is very pleased with it. At the same time there are two features which are quite marked on the cars when complete, and I feel will be a source of complaint. These are, the effects of prop. shafts which are not 100% in balance, and the exhaust boom at 30 m.p.h. With regard to the prop.shaft vibration, as you know this, in most cases, sets up a very unpleasant boom in the body. Some bodies are rather worse than others in this respect, and we have with the help of the Coachbuilders been able to effect quite a considerable improvement by attention to the body. This was very marked in the case of Lloyd George's car - body built by Abbotts of Farnham. At the same time we had to fit to this car two different prop. shafts before we were satisfied that we had done the best possible. In other cases the bodies do not boom badly, but the feel of vibration commences through the car, starting approximately at 55 m.p.h. and lasting until 60 m.p.h. is exceeded, and in all cases the vibration of the change gear lever is excessive. With regard to the exhaust boom - you will remember we spent considerable time on this feature on 35-EX chassis, but we feel that all production chassis suffer from the same complaint. It does appear to show up worse on a car fitted with the Continental Touring Saloon type of body, such as 35-EX and 37-EX. contd- | ||