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 performance of S.U. carburettors, a Chrysler-type fan, and various ignition plugs.
| Identifier | ExFiles\Box 82\1\ scan0313 | |
| Date | 9th December 1933 guessed | |
| - 3 - S.U. CARBURRETTORS LOP.EB.200 These have given no trouble, easy starting has been obtained from cold, metering upon acceleration gave no marked strong or weak positions, slow running has been generally even. The range of the jets at low speeds is limited. We have received fresh needles to give a greater range. The engine has been free from exhaust explosions on the over run. FAN STAGGERED BLADE - CHRYSLER TYPE. No undue noise is heard from the fan. The fan belt has not had to be adjusted. The distance of the leading edge of the blades from the matrix is 1.125" at the top and .750" at the bottom. No rivets in the blades have become loose. IGNITION PLUGS The following plugs have been tested: Two X 365 - 103 Short reach LODGE TWO X 366 - S10 Long reach LODGE Two 773s K.L.G. The plugs have not missfired upon acceleration or maximum speeds. There has been no sign of preignition. There was a tendancy at the finish of the mileage to missfire at low speeds, but no one plug could be accounted for it. The plug gaps were set to .015" and at 10.000 miles they were: LODGE .022 K.L.G..024 The centre electrode in each case having burnt. In appearance when dismantled it is very difficult to say which is in the worst condition. The small copper washer at the end of the insulation of the Lodge X365-103 had been burnt away. The cone insulation showed no defects. The X366-S10 and K.L.G. 773s both types mica insulations showed a slight fringe of mica protuding at the bottom joint to the electrode. The insulation was covered with a brown powder. No other defects can be observed. | ||