The running of a Wraith, detailing outstanding issues regarding performance, servo shudder, and clutches.
| Identifier | ExFiles\Box 7\1\ 600b 27 G V1 Mx Car-page28 | |
| Date | 10th June 1938 | |
| 600 Sev [Struck through] Sev [Struck through] Rm. {William Robotham - Chief Engineer} [Struck through] BY.21/G.10.6.38. [Signature] Mx {John H Maddocks - Chief Proving Officer} 's WRAITH. I attach hereto Mx {John H Maddocks - Chief Proving Officer} 's report on the running of 27-G-YI. The outstanding features which are still open to criticism are :- (a). Car Performance. (b). Servo operation from the point of view of servo shudder. (c). Improvement of clutches. (a). In regard to car performance, we have no solution for this at the moment. It will mean, however, that we have no further contribution to make in this direction at present. It is important to keep body weights as reasonable as possible in view of this. (b). Servo shudder - new Ferodo material RAD.13 appears to be an improvement in this direction. (c). Clutches - the Thermoid material appears to be certainly the best facing that we know of at the moment, and we are pursuing the occasional judders which Mx. {John H Maddocks - Chief Proving Officer} refers to, as from further work done it would appear that they have a relationship of oil leakage, as we have demonstrated that oil on the clutch face will cause these occasional judders, but has burnt off by slipping - the original condition of the clutch is restored. With reference to the inlet valve seat warping, this has been corrected by increasing the amount of material in the seating by using a venturi passage, which had been developed to improve performance. The delay in circulating this is due to the intervention of the holidays. BY. {R.W. Bailey - Chief Engineer} [Signature] | ||
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).