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, referencing a Phantom scheme on the 20 HP model.
| Identifier | ExFiles\Box 6\7\ 07-page033 | |
| Date | 28th February 1928 | |
| E.{Mr Elliott - Chief Engineer} from R.{Sir Henry Royce} c. to BJ. Wor.{Arthur Wormald - General Works Manager} BY.{R.W. Bailey - Chief Engineer} Hs.{Lord Ernest Hives - Chair} 45230 R3/M28.2.28 INDIA 3. X.5770 X.5070 X.5330 X.5080 X.5010 X.5000 In addition to the 6 items given in DA{Bernard Day - Chassis Design}/EV{Ivan Evernden - coachwork}/24.2.28., we ought to get some engine improvements: (7) Exhaust pipe like 'SS{S. Smith}' - Lec. 2S18. (8) Stiffer crankshaft. NOTE: Since we are getting such an enormous benefit from the wider webs, can we get a little more length on the main bearings (intermediate). (9) New head. I prefer this like your fig.1 and 11 - memo. E1/M25.2.28. I think we should make it as near as possible to '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) RR. 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 go 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 itwould be lighter and less costly. R.{Sir Henry Royce} | ||