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).
Outlining the agreed procedure for Bentley single cylinder unit and engine head development.
| Identifier | ExFiles\Box 133\2\ scan0175 | |
| Date | 16th September 1935 | |
| X1129 Hs{Lord Ernest Hives - Chair}/Wd.{Mr Wood/Mr Whitehead} Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} Hs{Lord Ernest Hives - Chair}/Smith. E/Tsn. E/Psn. E.2/HP.16.9.35. re Bentley Single Cylinder Unit and Bentley Development. The position of the above development was discussed and the question of finding some alternative head for the 3 valve Ramp. The following was the procedure agreed on:- (1) Wd.{Mr Wood/Mr Whitehead} will obtain if possible data from Rudge Whitworth regarding the difference in power output between heads with radial stems and heads having the valve stems parallel. He will endeavour to obtain a head with parallel valves to test. (2) The detonation characteristics of the Rudge Whitworth heads will be investigated at full throttle low speed and compared with the existing type Bentley and 2 valve Ramp heads. (3) E/Psn. will go ahead with modifications to provide overhead camshaft drive on the single cylinder unit arranged so as to swivel and couple up to different heads. The unit should be capable of running continuously at 5500 r.p.m. and for short bursts up to 6000 r.p.m. (4) E/Psn. will also go ahead with the necessary design work for testing out the 3 valve Ramp head as designed for the 8 in line Bentley. (5) E/Tsn. will go ahead with the design work for a shallow Pent-House head having three valves similar to the Ramp but with opposed sparking plugs and arranged for 7½ to 8 compression ratio. The effect of varying the stroke length between 4 and 4½" will also be investigated and the possibility of still further increasing the valve diameters by overlapping the head over the bore. This latter development is based on the agreement to have the cylinder block extended to allow for water in | ||