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).
The testing of a split piston design and a proposal for further experiments.
| Identifier | ExFiles\Box 77\3\ scan0004 | |
| Date | 30th October 1919 guessed | |
| x 3432. Extract from EH5/LG17.LO.19. --------------------- Piston with split on the non-pressure side. A set of these pistons are running on a car, They have run for 450 miles. This set we are running are excellent as regards absence of knocks. We have left the car outside all night and find that when it is started up it is very difficult to pick out any knock, what noise there is from the pistons disappears before the car has stopped popping and spluttering and is running evenly. We have done the worst things we know of to try and seize it up but have not been successful. The clearance we are running with on the fitting portion of these pistons to .006" to .004". With these clearance, of course, we should expect that some of these pistons will knock when cold. We consider this split piston is a hopeful proposition and we shouldlike Mr. Royce to confirm that he agrees with us continuing the tests with these pistons in parallel with other experiments. EH. | ||