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 and modifications of distributor and governor components.
| Identifier | ExFiles\Box 168\3\ img072 | |
| Date | 13th February 1939 | |
| -2- The 'Lucas' type finger with the DW.718 cam gives the best performance, however, it would be too big an alteration to introduce the 'Lucas' type finger at this stage, it should be included in future designs. If the cam to DW.718 is available, this should be used, if not, we can recommend the standard cam. Centre carbon contact in distributor head. In our last report we criticised the excessively sloppy fit of the carbon brush in its holder. This matter has now been attended to by By/RD. Governor. In order to obtain a suitable governor characteristic, it has been found necessary to use two springs for the governor weights, one coming into action later than the other. (See RM{William Robotham - Chief Engineer}/RC.{R. Childs}/MH.{M. Huckerby}13.4.38). This scheme has now been completed and issued to production (see Da.{Bernard Day - Chassis Design}15/G.26.4.38). This governor has a very good characteristic curve, but up-to-date has only had a very limited road test. This scheme was incorporated in those supplied to 'A' originally intended for the Wraith 'A' series. A distributor incorporating this governor has done 5554 miles on Six's. Wraith, 27.G.VI. and 3,786 on 28.G.VI. with no complaints. A modification to the governor frame DW.661 has also been issued in which the boss used for housing the governor spring spindle has been strengthened to prevent cracking. Vernier Adjustment. A vernier adjustment has now been provided to aid the initial setting of the distributor. Spring Drive. (distributor). The spring ring for retaining the driving plates in position was found to be too weak. A scheme has been issued experimentally (CD.857) in which the gauge of this ring is increased from .036" to .048". This drive was tested on S.E.V. and completed 15,000 miles test without trouble. we recommend this modification. RM{William Robotham - Chief Engineer}/RC.{R. Childs} | ||