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 Rudge-Whitworth unit, comparing the performance of a new camshaft against the original.
| Identifier | ExFiles\Box 133\2\ scan0181 | |
| Date | 9th November 1935 | |
| To - Rm.{William Robotham - Chief Engineer} c to HS{Lord Ernest Hives - Chair}/Edwards. (Struck through) X1129 Rm{William Robotham - Chief Engineer} (Signature, struck through) LC Smith (Signature) RUDGE-WHITWORTH UNIT. Attached are blueprints giving the valve lift curve of the new camshaft compared with the original and power curves taken with the new camshaft with various exhaust systems. The new camshaft does not give the timing asked for but in spite of the negative overlap the m.e.p. curve is a very good shape with appreciably higher m.e.p. at high piston speeds than the standard or close centres Bentley heads and slightly better than the High power head. These comparisons may be modified by motoring losses - which will be measured at the conclusion of the work when the 40 h.p. swinging field dynamometer is installed. The programme of work on this unit includes comparison of present head with penthouse and spherical heads, air consumptions, air flow of valves and ports, further power curves on camshafts giving Bentley and alternative timings, motoring losses, effect of induction pipe variations and complete calibration of the best of the three heads. Full details of the unit are given in report Hs{Lord Ernest Hives - Chair}/Wd.{Mr Wood/Mr Whitehead}1/GB.14.5.35. (Handwritten note) Should like to see M.E.P. comparison at same piston speed of high power head Rm{William Robotham - Chief Engineer} Attach Hs{Lord Ernest Hives - Chair}/Wd.{Mr Wood/Mr Whitehead} | ||