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).
Graph showing a 20HP power increase due to higher compression ratio, larger valves, and lower depression in the induction pipe.
| Identifier | ExFiles\Box 22\4\ Scan123 | |
| Date | 31th March 1927 guessed | |
| 20HP POWER INCREASE DUE TO HIGHER COMPRESSION RATIO, LARGER VALVES AND LOWER DEPRESSION IN THE INDUCTION PIPE. ENGINE N° 11-GII. OPEN EXHAUST CORRECTED N.T.P. B.H.P. B.M.E.P. STANDARD 20 H.P. (OPEN EXHT.) B.H.P. B.M.E.P. 20 HP ENGINE WITH LARGE (1.400 DIA) VALVES, 5.45 TO 1 COMP. RATIO & TWO ZENITH TRIPLE VENTURI HORIZONTAL CARBURETTORS. BRAKE HORSE POWER R.P.M OF ENGINE BRAKE MEAN EFFECTIVE PRESSURE (LBS/□") 4 | ||