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).
Experimental test report on the air silencer and distribution for a 25/30 HP engine.
| Identifier | ExFiles\Box 155\2\ scan0028 | |
| Date | 7th January 1937 | |
| To E.{Mr Elliott - Chief Engineer} c. to Da.{Bernard Day - Chassis Design} 1315 Rm{William Robotham - Chief Engineer}/CTS.{C. Trot Salt - Carburation}16/JH.7.1.37. EXPERIMENTAL TEST REPORT. 25/30 H.P. AIR SILENCER AND DISTRIBUTION. Parts under test. Combined air silencer and rocker covers to E.61022. Method of test. Direct comparison against present production systems for :- (1) Restrictions to breathing. (2) Distribution. (3) Noise. Results. (1) There is not sufficient restriction to cause any power loss, or any effect on specific consumption. (2) Graph No. S.14 shows the distribution curves of the present production 25/30 engine. Graph No.S.17 shows the distribution of the same engine with the air silencer and intake bend removed. There are two reason for the upsetting of the distribution. (a) The fact that the intake bend is parallel to the induction pipe. (b) There is only one support to the H.V. choke in the D.C.42 Stromberg carburetter causing bias effect. Graph No.S.15 shows effect of fitting the combined air silencer and rocker cover; a slight improvement. Graph No.S.16 shows the further improvement when fitting a second support to the H.V. choke in the | ||