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).
Investigation into the poor performance of post-war engines, specifically issues with the 40/50 chassis induction system and fuel distribution.
| Identifier | ExFiles\Box 50\3\ Scan021 | |
| Date | 24th February 1921 | |
| X.4305 To R. {Sir Henry Royce} and E. {Mr Elliott - Chief Engineer} from Hs. {Lord Ernest Hives - Chair} c. to CJ. c. to BN. {W.O. Bentley / Mr Barrington} and BY. {R.W. Bailey - Chief Engineer} c. to EP {G. Eric Platford - Chief Quality Engineer} and Da. {Bernard Day - Chassis Design} c. to EWT. for R.R. Inc. for sketch see original. Hsl/LG24.2.21. X4305 40/50 CHASSIS INDUCTION SYSTEM. X2565 Whilst I was in the U.S.A., it was proved that, on the average, post-war cars were worse than pre-war cars as regards running on the petrol obtainable in that country. There has been no alteration to the design of the induction pipe and carburetter or heating arrangements, so the only thing one could think of at the time which could make any difference, was the modification to aluminium pistons. From the tests we have made at the works lately, we have found there are other reasons why post-war cars might be worse. When I returned to Derby, the Test Dept. were having a lot of trouble with 40/50 engines on the Test Bench because they could not maintain the [s]exgt[/s] maximum torque at low speeds and because of them missing fire when picking up [s]low-speeds-and-because[/s] after being run a short time full power low speeds. They found that this trouble was solely due to bad distribution. The distribution was so bad that when the mixture was weakened, some cylinders would be firing vigorously and others popping due to weakness. The engine used for experimental tests was examined and was found to be very good as regards distribution under various conditions. A series of tests were made changing over various units from the experimental engine and it was found by the Test Department that the throttle was the unit which made the difference between good and bad distrib- Contd. | ||