Modifications to the Japan S. Engine, specifically the connecting rod and cylinder head.
| Identifier | ExFiles\Box 5a\1\ 01-page067 | |
| Date | 14th February 1931 | |
| JR. {Mr James Royce} FROM E. {Mr Elliott - Chief Engineer} SECRET X5770 E1/14.2.31. C. to SG. {Arthur F. Sidgreaves - MD} HCR. C. to HB. {C. E. Harcombe} BY. {R.W. Bailey - Chief Engineer} HY. {Tom Haldenby - Plant Engineer} JAPAN(Experimental Engine) S. ENGINE We send you herewith a further print of Lec. 2853., showing certain modifications suggested by HY. {Tom Haldenby - Plant Engineer} and RASC. to facilitate production, together with some other points which we set out as follows: CONNECTING ROD E.I.C.S. Derby prefer the scheme shown for preventing the heads from turning as being the easiest to produce. We see no objection providing the thickness of the metal on the rod at the point where the section changed is well maintained. CYLINDER HEAD. (a) Derby wish to reduce the height of the cast iron wall standing up round the valve gear to a minimum as this feature is a source of casting scrap. We had the same idea in mind with a view to reducing the weight and we have therefore cutout the feature which was bolting onis face up. (b) Derby prefer the water jacket on the induction side to make one slope from rocker box to base as in sketch to allow for bigger cores and to simplify the moulding around the inlet flanges. We are in agreement with this as we feel there is perhaps not sufficient room in our cylinder heads for unimpeded water flow unless we tap off at intervals into an external water pipe. At the same time we have increased dimension A. {Mr Adams} above the exhaust bend when had become less than we thought desirable. (c) Derby wish to bring down the induction flanges below the top face. This allows them to surface grind both on a circular table. We have been able to do this by reason of the next item, and by canting the flanges over a little. (d) Derby asked if the spark plug drilling on the induction side could be same as exhaust. We see no objection to this as we do not think the difference in the plug position would be detected in practice, and also this item helps (c). (1) | ||
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).