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).
Potential engine improvements and design changes for a 20 HP Phantom scheme.
Identifier | ExFiles\Box 5\4\ 04-page196 | |
Date | 28th February 1928 | |
E.{Mr Elliott - Chief Engineer} from R.{Sir Henry Royce} c. to BJ. Nor. BY.{R.W. Bailey - Chief Engineer} Hs.{Lord Ernest Hives - Chair} 45080 HS{Lord Ernest Hives - Chair}/M28.2.28 INDIA 3. X.5170 X.5070 X.5230 X.5080 X.5010 X.5000 In addition to the 5 items given in DW/EV{Ivan Evernden - coachwork}/24.2.28., we ought to get some engine improvements: (7) Exhaust pipe like 'SS{S. Smith}' - Lec. 251S. (8) Stiffer crankshaft. NOTE : Since we are getting such an enormous benefit from the wider wood, can we get a little more length on the main bearings (intermediate). (9) New head. EL/25.2.28. I prefer this like your fig.1 and 11 - memo. 'SS{S. Smith}'. Perhaps we can keep the ignition exactly as at present except the slight change in position of plug. I think we must bring the induction pipes to the other side, slotted type, either under or over as you find better. We have not tested the combination of : (a) Increased size of valves. (b) M.L. carburetter. (c) Slotted intake. (I mean the intended Phantom scheme on the 20 HP.) I do not know if we have investigated all our troubles of the carburetter and steering fouling, and if there is height and room to get the carb. and controls satisfactory. It is possible we are losing some power by heat to the ingoing air in the cyl. block and hot spot, but I have not seen how much. Every consideration seems to favour your fig.1. which gives a high position of the induction pipe. I certainly should do all that is necessary for this unless there are some unsurmountable difficulties. I do not think time will allow us to have a new crankchamber pattern, but I understand you may want to alter the position of some of the studs, though it is not exactly clear to me why, because the double outlets are still the same side of the engine. If we have to make a new chamber pattern it would be as well to make the design of the simpler stud pattern, as I understand it would be lighter and less costly. | ||