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).
Planned tests on carburettors, a 4-cylinder 'Thumper' engine, and induction pipes.
| Identifier | ExFiles\Box 174\3\ img298 | |
| Date | 3rd June 1941 | |
| Rm.{William Robotham - Chief Engineer}7/ST.3.6.41 - 4 - 21. CARBURATTER TESTS. The tests to be done on consumption are:- 1 - Blanking plate on 9.B.V. 2 - Various sizes of induction pipe. 3 - Ultra long reach plugs. For idling, we still want a report on the effect of:- 1 - Balanced holes between the two halves of the carburetter. 2 - Ultra long reach plugs. 3 - Timing. 4 - Reduced dimensions of exhaust manifold. 22. 4 CYLINDER THUMPER. Test with half the 8-cylinder exhaust system. Check compression ratio head, and if exhaust system does not eliminate the engine roar at 30, try lowering the pressure ratio slightly. If this fails, a crankshaft damper should be tried. Rm{William Robotham - Chief Engineer}/Wym.{G. Harold Whyman - Experimental Manager} should remind Jnr.{Charles L. Jenner} that, if he is going to give us a correct head design for the 3.5 bore, the details of the present thumper head must be modified. Rm{William Robotham - Chief Engineer}/Wym.{G. Harold Whyman - Experimental Manager} will give Rm.{William Robotham - Chief Engineer} a figure for petrol consumption on an average run, and the mean maximum time speed. Also the top gear performance compared with the 12 H.P. Rover. A spare wheel cover is being obtained for this car and is promised for Friday. Rm.{William Robotham - Chief Engineer} is going to instruct another 4-cylinder engine 3¼" bore, with the object of ascertaining whether a saleable proposition can be achieved. It is considered that the smaller engine would not be worth putting on the market at the price it would have to be sold with the Senior Pieces. He would like a list of the parts available towards this engine, that are at present in existence. 23. DUPLEX INDUCTION PIPE. It was agreed that this should be got up to a reasonable degree of performance on the test bed, and should then be tried on the road. In the meantime, Rm{William Robotham - Chief Engineer}/Wym.{G. Harold Whyman - Experimental Manager} should be able to tell us what a small induction pipe is worth for idling and consumption. | ||