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 from Allen & Simmonds Ltd. to H. Swift Esq. detailing piston improvements in lorries.
| Identifier | ExFiles\Box 77\1\ scan0033 | |
| Date | 28th October 1920 guessed | |
| H.{Arthur M. Hanbury - Head Complaints} Swift Esq., 2. long use of the pistons in their steam tractors, but have now substituted petrol lorries for the delivery of their goods, fitted one of their six lorries some six months ago. They took the worst of their fleet, an "Aveling" 4-ton, and whereas the lubricating oil used was 30 gallons on an average of 800 miles run, it is now down to 5 gallons for the same mileage. This was the worst pulling lorry of the six, and the Chief Engineer states it is now by far the best, and he estimates he has 20% more power. Of course, with the elimination of lubricating oil from the top of the pistons, as you know, you overcome the sooting up or carbonizing of the sparking plugs, and cust out the necessity of taking the engine down so frequently for cleaning our carbon deposit. In the case of the Reading Tramways two rings per piston only were used, 1/8" width of rubbing surface. In the case of Messrs Wethered's "Aveling" lorry, a 4-cylindered job, only one ring per piston is used. There is absolutely no trouble with the temper of the springs being affected, and wear and tear of rings is well below normal. I would like to shew you these pistons personally at your earliest convenience, because I am sure you will admit, by substantiating the facts we have mentioned, that we have made a very important improvement indeed in the internal combustion engine. Believe me, Yours faithfully, For ALLEN & SIMMONDS (READING) LTD [Signature] MANAGING DIRECTOR | ||