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 performance issues of an experimental exhaust-heated throttle, particularly regarding poor fuel distribution in cold conditions.
| Identifier | WestWitteringFiles\G\September1921\ Scan76 | |
| Date | 1st September 1921 | |
| To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c. to CJ. c. to R.{Sir Henry Royce} c. to Dn. c. to BY.{R.W. Bailey - Chief Engineer} c. to EF. c. to EWT. for R.R. Inc. ORIGINAL. Hs{Lord Ernest Hives - Chair}5/LG20, 9. 21. EXHAUST HEATED THROTTLE. X4305 We are not able to obtain much good results from the exhaust heated throttle made to LcC.1418, as we can from the experimental exhaust heated throttle which was produced by fitting a copper jacket to a present standard 40/50 throttle. The fault we have with the exhaust heated throttle is that the contour of the throttle has been altered so that the distribution when the engine is cold is bad. Under cold condition we collect three times as much liquid petrol from the 4, 5 and 6 cylinders than we do from 1, 2 and 3. Without the "Dorris" scheme for collecting petrol, this throttle is quite impossible with 20% paraffin mixture, cold engine. The "Dorris" scheme improves it tremendously, but it is not as good as the experimental throttle with the Dorris scheme. We have not yet been able to appreciate any advantage in using the 1 1/2" pipe. With our experimental exhaust heated throttle fitted to a standard 2" induction pipe and fitted with the Dorris scheme, we are able to start up a cold engine, open up immediately to 500 R.P.M. full throttle and maintain maximum torque. We have been able to do this on two sets which we have made. We have tried fitting pegs in the exhaust heated throttle casing in order to correct the distribution similar to what proved successful on the 40/50. contd:- (upside down text) R.R. 235A (50 T S.H. 986. 19-2-21) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 3008 | ||