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 and proposed modifications to the 20 HP engine's exhaust and induction systems.
| Identifier | ExFiles\Box 48\4\ Scan043 | |
| Date | 7th April 1924 | |
| 4227 To HS.{Lord Ernest Hives - Chair} from R.{Sir Henry Royce} c. to CJ. R1/M4.7.24. 20 HP. EXHAUST AND INDUCTION TESTS. X.4238 X.4227 With regard to the above tests I should like to know if the freer exhaust, such as you have with the 3 pipe arrangement, improves the slow running of the engine, also does the silencer with cutout open (as 5-G-11) give better power than no exhaust pipes at all, that is to say, no manifold on the engine. We are hoping for some further benefit form the use of an ejector in the exhaust system. For this you will require a new cylinder head. We shall shortly send the necessary drawings. In addition to increase of power we are particularly anxious to find out what benefit variations to the exhaust or cut-out may have on slow running and petrol economy on the road. EXHAUST HEAT TO THROTTLE ETC. In addition to the alterations to the exhaust we are modifying the induction so as to give better distribution cold, and quicker and more effective heating of the throttle by the exhaust, and we want you to find out whether there is any difference between the 2 pipes shewn in the accompanying sketches. The more complicated scheme extends the heat further along the induction pipe at the bottom, and might give some further advantage in distribution, slow running, or petrol economy, and through better distribution it may improve the power at low speed full throttle running. R.{Sir Henry Royce} The sketches referred to above will form a LeC. drawing and will follow under a separate memo. | ||