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).
Tests of an exhaust heated throttle and draining scheme, comparing its performance against a standard engine and a 20% mixture.
| Identifier | ExFiles\Box 50\3\ Scan182 | |
| Date | 1st September 1921 | |
| Contd. -3- Hsl/LG1.9.21. ----------- with the exhaust heated throttle and the draining scheme for the pipe, the other was a standard engine. The car fitted with the exhaust heated throttle and the draining scheme immediately it was started up could be put on to full throttle without any popping, spluttering or missing fire. It had a very much better get-away than the standard car with the very best petrol we can obtain. The standard car with the 20% mixture was impossible; it took 10 to 15 minutes before the car was fit to run. We have also tried a car with the exhaust heated throttle without the draining. This is not nearly as good as when the draining is fitted; it is alright when the throttle gets hot but the warming up process is unsatisfactory. We are now carrying out tests to prove whether we get any crankcase dilution and if so, how much. It should be realized that cars in Wintertime in U.S.A. are only used in towns, the roads outside being practically impassable. This means that there is an enormous lot of stopping and starting. We have heard from Mr. Olley that they are also experimenting with the "Dorris" scheme and their results confirm those which we have obtained. They are arranging to test a car with a very similar arrangement to what we have used. With reference to the charts attached herewith, it will be seen that if the throttle in the exhaust pipe is adjusted so that it opens fully, there is a danger, if the car is run con- tinuously full throttle low speeds, of the temperature of the throttle dropping even below the temperature of the water. contd:- | ||