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 power output and detonation for 116° and 110° camshafts on the 'China' engine.
| Identifier | WestWitteringFiles\T\2July1929-December1929\ Scan109 | |
| Date | 1st November 1929 | |
| To R.{Sir Henry Royce} from HS{Lord Ernest Hives - Chair}/ACL. c. SS.{S. Smith} c. Sor. E.{Mr Elliott - Chief Engineer} c. Da.{Bernard Day - Chassis Design} BY.{R.W. Bailey - Chief Engineer} HS{Lord Ernest Hives - Chair}/ACL2/AD5.11.29. x5771. x5090. "CHINA" ENGINE - CAMSHAFT COMPARISONS ON THE HIGHER OUTPUT ENGINE. We have completed a test on the China engine comparing the power output given by 116° and 110° camshafts. The 116° camshaft has the advantage above 2600 R.P.M. The power peak is given at approx. 3200 R.P.M. giving 75 B.H.P. or 5 B.H.P. more than the maximum reading with the 110° camshaft. at 3400 R.P.M. the 116° camshaft has the advantage of 9 B.H.P. over the 110° at the same speed. The power peak of the 110° camshaft occurs at 2850 R.P.M. At speeds below 2600 R.P.M. the results are in favour of the 110° camshaft, (std.) to the extent at the most of 2 B.H.P. We find the 110° camshaft is noticeably worse for detonations - on the test bed, not yet road tested - at low full throttle speeds. The compression ratio was 5.25/1. This would indicate that a higher compression ratio could be employed with the 116° to reach the same degree of low speed detonation or conversely the 110° camshaft would have to work with a lower compression ratio than permissible with the former. It therefore might be | ||