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).
The running conditions and compression pressure tests for 'SS' Engine No. SS-3.
| Identifier | ExFiles\Box 92\2\ scan0022 | |
| Date | 28th September 1928 | |
| To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/ACL. c. to BJ. Wor.{Arthur Wormald - General Works Manager} c. to E.{Mr Elliott - Chief Engineer} DA.{Bernard Day - Chassis Design} c. to BY.{R.W. Bailey - Chief Engineer} (7771) Hs{Lord Ernest Hives - Chair}/ACL1/LG28.9.28. 'SS{S. Smith}' ENGINE. X790 X7770 Engine No. SS{S. Smith}-3 - Total running time to date = 38¼ hrs. Running conditions. Claudel Hobson carburetter (Eagle IX) Hop-spot in action (water temp. = 75°C) Exhaust manifold fitted, and bed exhaust system. 116° Camshaft - Cam forms E.77854/5. The compression pressures of this engine have been ascertained throughout the speed range for each individual cylinder; the results being tabulated below :- Max: comp: pressure (Lbs/sq. in.) R.P.M. | No.1. | No.2. | No.3. | No.4. | No.5. | No.6. 3000 | 86.5 | 86.5 | 88.5 | 88.0 | 86.5 | 84.0 2500 | 90.5 | 93.0 | 93.5 | 95.0 | 92.5 | 90.5 2000 | 94.5 | 95.5 | 95.0 | 95.0 | 95.0 | 94.0 1500 | 94.5 | 94.0 | 95.0 | 95.0 | 93.0 | 93.5 1000 | 86.5 | 86.5 | 88.5 | 87.5 | 86.5 | 87.0 750 | 89.0 | 88.0 | 89.5 | 89.0 | 88.0 | 89.5 The average figures for above are plotted on V.431. Tests to ascertain the mechanical effcy. have also been carried out, the results being given on V.432. The method used was that in which the loss of torque is noted when the cyls. are cut out one at a time, the speed being kept constant. The Claudel Hobson carb. had been removed and a std. Phantom carb. fitted in its place, by means of a contd:- | ||