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).
Engine pre-ignition, spark plug issues, and performance feedback on braking and shock dampers.
| Identifier | ExFiles\Box 5a\2\ 02-page221 | |
| Date | 10th March 1930 | |
| Handwritten notes: Top Left: To: Mr. Hs{Lord Ernest Hives - Chair} From C.S. ... Hs{Lord Ernest Hives - Chair} Top Center: (By) mailed By v5548 Please return (Dt) noted On (E) noted (AE) Top Right: HS{Lord Ernest Hives - Chair} Typed Document: Hotel de France, Châteauroux. 10/3/30. We have to-day received your telegram: DISPATCHED TO ABOVE ADDRESS EXHAUST FITTINGS AND SEMOIST SCREWS HIVES. We have had definite signs, as you will see in today's report, of pre-ignitions. We are in the old trouble of the engine continuing to run after switching off when coming to rest. This has become noticeable the last 2 days. The centre electrode of the plugs when examined after the finish of the run last night, have the impression that they had been overheated. All except No 6 gave this sign. These plugs are the special Lodge non corrosive type. We have not been able to blame the erratic slow running to the plugs that has occurred and been reported occasionally, and we cannot find any failure of the insulation having taken place, but the centre electrode is definitely showing more signs of burning than we think has previously been experienced. When driving at 50/60 M.P.H. we have frequently switched the ignitions off to obtain data of pre-ignitions, and the engine has immediately ceased fire, proving that we are not in trouble with pre-ignition at high sustained speed. The Azemite R.A. wires fitted to MDC's instructions must on no account be standardised. The cable is an utter failure from the insulation point of view, there are now circles opening out almost the full length of the wire, due to the lacquered covering breaking up. This has been distrusted for some time. We should very strongly advise not to let another test go through with this wire, as we believe most of our troubles with erratic running is the short circuiting of the... We are, after getting used to the extra pressure on the foot pedal, quite satisfied with the braking effort of the car after fitting the reduced leverage for the rear brakes. I definitely skidded the rear wheels braking from 40 to ... The Servo dumper, Experimental Depcis design, has entirely eliminated the noise from the return of the servo mechanism. We are very pleased with it and we should advise very strongly to have similar ones fitted to the experimental cars. The only fault, as explained to "MDC", was that the bent filtering design had not allowed for the inrush of air when the brakes are applied, so there should be no restriction to the piston on its outward stroke. We have forwarded drawings and a note to "MDC" re this. We are getting another pletch out for the edification of Mr. Day. We are dealing with R-R's suggestions and problems of the shock dampers. We received his memo Hs{Lord Ernest Hives - Chair}/Hsi/Ms.17/4/30 this morning along with the drawings. We appreciate his remarks, but at the same time we have had good results if the flow from the Hifay is correct. We are going thoroughly into this matter. May we draw your attention to the lagging... | ||