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).
Two proposed modifications to the Japan 3 engine concerning the combustion chamber and crankpin.
| Identifier | WestWitteringFiles\V\October1930-February1931\ Scan343 | |
| Date | 16th February 1931 | |
| FROM E.{Mr Elliott - Chief Engineer} G.{Mr Griffiths - Chief Accountant / Mr Gnapp} to SS.{S. Smith} WDR. C. to HS.{Lord Ernest Hives - Chair} BY.{R.W. Bailey - Chief Engineer} HV. SECRET ORIGINAL JAPAN 3. ENGINE. E1/M16.2.31. x577o Please find herewith print of LeC. 2875. shewing two modifications. The first is in connection with the combustion chamber. We propose to fill in the undercut we have at present to simplify the machining of the interior of the combustion chamber, and at the same time we want the compression space smaller. The origin of the undercut was to leave sufficient room round the valve seat without encroaching on the gasket dimensions too much. We think the valves will be satisfactory however as shewn on LeC. 2875. The other alteration is a reduction in the crankpin dia. to enable the con. rod big end to pass comfortably through the cyl. bore. E.{Mr Elliott - Chief Engineer} | ||