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).
Comparison of the power output between 'Japan' and 'China' type engines.
| Identifier | ExFiles\Box 5a\5\ 05-page225 | |
| Date | 1st November 1929 | |
| X5771 To S. from Hs{Lord Ernest Hives - Chair}/GHP. c. SS.{S. Smith} c. Sor. E.{Mr Elliott - Chief Engineer} c. Ds. EV.{Ivan Evernden - coachwork} HS{Lord Ernest Hives - Chair}/GHP9/ADW.11.29. POWER OUTPUT OF "JAPAN" ENGINE. The power curve V.743. shews a comparison between the output of the "Japan" engine as fitted to 18-14 and the higher output "China" engine when run under similar test conditions. The "Japan" engine is fitted with a six-port turbulent head and a top-feed slotted induction pipe. The valves are almost the same size as a standard "China" engine, the inlets being 1.350" dia. and the exhausts 1.250" dia. The higher output China engine has a standard type head with slightly increased ports, larger valves (1.400" dia inlet and exhaust) and on enlarged induction passage (1.200" dia) through the cylinder block. A standard induction pipe is used which is chamfered out at the ports to match up with the enlarged ports in the cylinder head. Both engines are fitted with a standard 110° camshaft, a 20 H.P. R.R. carburetter having enlarged chokes and air valve ports which give 46% more area than standard. The compression ratio of each engine is 5.25. The curves represent open exhaust figures. It will be noticed that the power developed by the Japan engine is greater at all speeds than that of the China engine, although the former is handicapped at | ||