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 a supplier about a device designed to accurately meter heat to simulate road conditions during engine testing.
| Identifier | ExFiles\Box 123\1\ scan0121 | |
| Date | 6th September 1938 | |
| R.P.81 S. SMITH & SONS (Motor Accessories) LTD. CRICKLEWOOD WORKS, LONDON, N.W.2. CONTINUATION NO. 1 Messrs. Rolls-Royce Limited. 6th September 1938. The job we are putting up is intended to enable you to make a really accurate job, that is, we are attempting to meter heat with precision, and therefore all extreneous sources of heat must obviously be eliminated. Another point which we find some difficulty with manufacturers is that our unit is essentially a device for the road and has little relation to test shop conditions. Heat as a general rule is fairly controllable in the test shop. It is when you get out in the frost or try to climb steep hills on summer days with a heavy load that the test shop conditions are not comparable. We would like you to get the device to give the conditions you customarily desire and then try on a car, that is, out and about in all conditions of weather. In theory and under actual conditions it should give improved consumption, better pick-up and get-away, quicker warming up, freedom from carbon deposit and cylinder wear. We venture to suggest that none of these characteristics can be discovered successfully in the test shop. We can summarize the above as under:- 1 - Merely a method of introducing accuracy and providing a datum from which to set the carburetter closer to the ideal. 2 - Not intended to create new conditions, i.e. overheat mixture or disturb knwon requirements. 3 - It eliminates variations or differences of conditions introduced by seasons and day to day changes of climate. 4 - By placing the air intake near the louvres or bonnet ventilator, cold air can be drawn from outside the bonnet so avoiding the effects of under bonnet temperatures in hot weather or climates. 5 - Total heat supply to the mixture can be metered accurately and known. The charge is prepared as soon as the engine is running. We trust the above will be of use to you and await your further news when you have had an opportunity of investigating this device. Yours faithfully, For S. SMITH & SONS (MOTOR ACCESSORIES) LIMITED. [Signature] THERMOSTATIC CONTROL DEPARTMENT. | ||