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).
Bench tests of new 40/50 induction and exhaust pipes, detailing poor performance and distribution results.
| Identifier | ExFiles\Box 75\2\ scan0288 | |
| Date | 1st July 1922 | |
| To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c. to CJ. c. to E.{Mr Elliott - Chief Engineer} c. to Da.{Bernard Day - Chassis Design} c. to BY.{R.W. Bailey - Chief Engineer} X2758 Hs{Lord Ernest Hives - Chair}7/LG26. 7. 22. 40/50 INDUCTION PIPES X2758 X4305 X4390 We have carried out tests with induction pipes and exhaust pipes as shown on Lec.1550. We have used the standard 40/50 carburetter in conjunction with the butterfly throttle valve. So far the tests have been on the bench. The results we have obtained with this arrangement are not as good under any conditions as we can obtain with our present standard arrangement. The horse power obtained from the engine is not, at any speed, greater than with the present standard arrangement and at some speeds it is less. The distribution of the pipe, even with the hot spot throttle working is poor. It was difficult to obtain even torque at 500 or 750 r.p.m. owing to No.4 and No.6 cylinders being very strong. We also found that the distribution was influenced by the angle of the butterfly valve i.e., with half-open throttle we obtained a different result to full throttle. We have tried the butterfly in different positions. At present we are fixing up a hot spot between the throttle and the induction pipe. We believe that the position for the hot spot is as close to the carburetter as possible and certainly before the junction in the induction pipe. We shall be sending five figures, comparative horse-powers and further particulars immediately. contd:- | ||