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).
Power readings for a standard 8-litre engine Y.X.5106 with a 5.1 compression ratio.
| Identifier | ExFiles\Box 21\2\ Scan076 | |
| Date | 22th January 1931 | |
| 22nd January, 1931. POWER READINGS TAKEN ON STANDARD 8-LITRE ENGINE Y.X.5106. (5.1 COMPRESSION RATIO). OPEN TEST SHOP EXHAUST PIPE. BAROMETER 29.9. -------------------- Handwritten: 115x110 110 x 140 7883 cc TABLE: R.P.M. B.H.P. MAGNETO SETTING. DELCO SETTING. 3,500. 192.25 90 45° advanced. 47°30' advanced. 3,400. 194.5 " " " " 3,300. 194.5 " " " " 3,200. 193.75 " " " " 3,100. 191. " " " " 3,000. 188.5 102.5 " " " " 2,750. 178.75 " " " " 2,500. 164. 107 " " " " 2,250. 150. " " " " 2,000. 131.25 107 " " " " 1,750. 123.5 " " " " 1,500. 100. 110 " " " " 1,250. 83.5 109 30° " 32°30' " 1,000. 66.5 109 " " " " 750. 51. 112 20° " 22°30' " 500. 33. 109 14° " 16°30' " Handwritten: I.O. 6.5° Early E.C. 10.5° LATE . Horses/Litre/1000 Revs x 13 (66.5 x 13) / 7.983 65.6 | ||