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).
Progress report on the single-cylinder development of an Overhead Inlet Side Valve Exhaust engine.
| Identifier | ExFiles\Box 134\2\ scan0121 | |
| Date | 20th August 1937 | |
| By.{R.W. Bailey - Chief Engineer} from Rm.{William Robotham - Chief Engineer} c. Sg.{Arthur F. Sidgreaves - MD} c. Hs.{Lord Ernest Hives - Chair} c. Da.{Bernard Day - Chassis Design} c. Mx.{John H Maddocks - Chief Proving Officer} V29 OVERHEAD INLET SIDE VALVE EXHAUST ENGINE. In view of the fact that we are designing this type of combustion chamber into the new Phoenix engine as an alternative to the push rod in-line head, it may be of interest to indicate the progress which has been made on Single Cylinder work on this unit recently. The big disappointments of the Overhead Camshaft engine have been:- (a) It does not give any more power at low speeds than the standard engine. (b) At high speeds it is very susceptible to exhaust back pressure. We therefore made a special investigation to find out how the high power head behaves in these two respects. The attached preliminary report indicates that with equal detonation we can get over 7% more power out of the high power head at 1000 R.P.M. and 20% at 4000 R.P.M. We have already found that by modifying the duration of the exhaust valve opening we are far less susceptible to exhaust back pressure than with the present standard Bentley. These results may be altered on the full scale engine but they are sufficiently promising to encourage us to go ahead. Tests will have to be repeated when we know exactly what shape of cylinder head will be necessary to fit into the limitations of the 6 cylinder in-line engine. Rm.{William Robotham - Chief Engineer} | ||