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 a 116° camshaft against a standard 110° camshaft on a standard China engine, detailing performance differences.
| Identifier | WestWitteringFiles\T\2July1929-December1929\ Scan138 | |
| Date | 12th November 1929 | |
| To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/ACL. c.c. Sg.{Arthur F. Sidgreaves - MD} c. Wor.{Arthur Wormald - General Works Manager} E.{Mr Elliott - Chief Engineer} c. Da.{Bernard Day - Chassis Design} By.{R.W. Bailey - Chief Engineer} ORIGINAL Hs{Lord Ernest Hives - Chair}/ACL9/AD12.11.29. X5771- X5090. 116° CAMSHAFT ON STANDARD CHINA ENGINE. We have compared the 116° camshaft (E.55362) with the Std. 110° camshaft on the Std. China engine. Curves are given on appended print V.745. The increase of power at the high speeds given by the 116° camshaft is not so marked on the Std. engine as when used in conjunction with larger valves and a larger carburetter as shewn in our report of 5.11.29. In this case we get an increase at max. power of 2.3% whereas on the large valve engine and large carb. we obtained 6%. The 116° camshaft raises the R.P.M. at which the power peak occurs by 5% but when used in conjunction with larger valves and carburetter the peak is raised by 12.3%. The std. crankshaft has the advantage at low speeds. This is better shewn up by referring to the B.M.E.P. curves where we see the advantage is to the extent of 8.3% at 1000 R.P.M. Actually this gain in M.E.P. at low speeds is quite appreciable on the road, whereas it is necessary to have a substantial increase at high speeds to appreciate | ||