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).
Design of weir vs. slot type induction pipes for the EAC.14 engine.
| Identifier | ExFiles\Box 13\3\ 03-page012 | |
| Date | 7th January 1928 | |
| R.{Sir Henry Royce} from E.{Mr Elliott - Chief Engineer} c. to B.J. Hs.{Lord Ernest Hives - Chair} BY.{R.W. Bailey - Chief Engineer} 47070 E2/M7.1.28. EAC.14 - INDUCTION PIPE. X.7070 X.8070 The weir or slot type induction pipe at present being tested on an EAC.14. engine was designed as a test model of what we now know as EAC.10., and hence the carburetter is very high up, as in fig.1. SEE ORIGINAL FOR SKETCH. Starting from first principles we believe a slot type induction pipe for EAC.14 should be made as in fig.2., and this is what we are drawing at the present moment. A pipe like fig.2. gave excellent results when slot pipes were first tested. Derby will be able to tell us, as they have models of both patterns, which is to be preferred. A short vertical length of pipe can be inserted in fig.1. to bring the carb. down to the same height as fig.2. We cannot see that there should be any advantage in the weir as compared with the slot underneath provided always that there is sufficient length of feed pipe between carburetter and manifold; we should rather expect some loss of power with the former. With the slot underneath the manifold can be made to drain either into the carburetter or into the engine as desired. SEE ORIGINAL FOR SKETCH. We must point out that with the under type slot the length is limited to 6", owing to the proximity of Nos.3 and 4 sparking plugs. This however was the length of the slot on the successful pipe tested. SEE ORIGINAL FOR SKETCH. E.{Mr Elliott - Chief Engineer} | ||