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).
Modifications to the Japan 3 cylinder head compression ratio and starting torque.
| Identifier | ExFiles\Box 103\4\ scan0069 | |
| Date | 1st January 1931 | |
| X 5080 BY.{R.W. Bailey - Chief Engineer} FROM E.{Mr Elliott - Chief Engineer} E4/M20.1.31. C. to SG.{Arthur F. Sidgreaves - MD} WOR.{Arthur Wormald - General Works Manager} HS.{Lord Ernest Hives - Chair} JAPAN 3. - CYLINDER HEAD AND STARTING TORQUE. In reply to your recent memo. concerning the starting torque please note we will look into the question of what modification is required. Regarding the question of compression ratio the Japan 3. cyl. head should be produced with 5.25 to 1 by suitably adding to the thickness of the floor of the water jacket. The design has been made with 5.5 to 1 so that this latter ratio can be obatined if desired. E.{Mr Elliott - Chief Engineer} | ||