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).
Progress report on component testing including rear axles, cylinder bore wear, and a four-cylinder engine.
| Identifier | ExFiles\Box 109\1\ scan0181 | |
| Date | 24th November 1942 | |
| -cont'd.{John DeLooze - Company Secretary}- -5- Ra/Wym.{G. Harold Whyman - Experimental Manager}1/OH.24.11.42. Rear Axle. We have had no further failures with axles other than the one reported on 30.G.VII. after 70,000 miles. The simplified thrust bearing has now run 44,650 on 9.B.V., 39,250 on 30.G.VII. and both are still running. We would point out however, that on 9.B.V. the pre-loading does not remain consistent in other words the Axle alternates between being quiet and noisy consistently. Tyres. The position of tyres is as previously reported. Petrol Consumption. The position is exactly the same as stated in the last report. 3.B.50. which is covering a considerable mileage in your own hands consistently averages 19 miles per gallon. Cylinder Bore Wear. Tests have been and are still being run on cars with various inserts and chromium plated bores and the following figures are those obtained by measurement and based on 50,000 miles running. Material of Bores. Average Bore Wear. Hi-Chrome. .0009" Chrome Plated. .0017" Brividium. .0054" Nickel Chrome. .0065" Standard. .0090" Phos. - Chrome. .0097" From these figures it will be seen that from the cost and wear point of view chrome plating of the bores is definitely desirable. FOUR CYLINDER ENGINE. The four cylinder engine fitted in 1.RT.1. has now run 13,867 miles and the only trouble it has given us has been the collapse of the valve springs after 13,000 miles. We are not in a position to do any carburetter development work to improve petrol consumption which at the moment is approximately 19 1/2 m.p.g. It should however be appreciated that this 14 HP. engine has been fitted in a car of 31 cwts. with an axle ratio of 10 x 43 and 6 x 16 tyres. The 10 HP. B. 40 engine has just been fitted into Cont'd.{John DeLooze - Company Secretary} Austin 10 Chassis and preliminary runs show that it | ||