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).
Review of the Bosch Battery Ignition system, its applicability to the current chassis, and suggestions for improvements.
| Identifier | WestWitteringFiles\G\June1921\ Scan38 | |
| Date | 21th June 1921 | |
| To R.R. of America Inc. from R.{Sir Henry Royce} -3- R2/021/6/21 Contd. BOSCH BATTERY IGNITION. X.4275. Regarding the Bosch battery ignition, I was pleasantly surprised how easily this was applicable to our present chassis, and how by their recent small modifications they were able to make it meet our wishes. I strongly recommend that you fit this to future cars since they seem to have done well in overcoming the deficiencies by adopting some of our arrangements. High Tension Distributor. X.4275. X.800 X 3309. One of the chief defects still remaining appears to be the Jump spark distributor is blind, that is, no one can see the distance and concentricity between the rotor and the distributor head. We notice you have fitted electrodes of some better metal. We do not know whether this is platinum, or silver, or nickel. Platinum of course is preferable, but is so extremely expensive that one feels inclined to try pure nickel or monel metal electrodes. Safety from Backfiring. X.4275. X 800. We also notice that you have added our trailing horn to the distributor rotor to prevent backfiring on the make. Care should be taken in arranging the timing of this that the normal spark takes place on the first ½" of the rotor. General Mechanical Construction. X. 4275. Regarding the general construction, we always had the impression that the bearing for the camshaft should be contained in the casing that carries the distributor head, so that the Bosch arrangement is entirely wrong unless the workmanship and condition of the parts are excellent (in our arrangement we have been careful to put a little ball bearing direct under the cam) To depart from such an arrangement has only been done for expediency, and to utilise the wonderful adaptability of this ignition to the parts on the present chassis. it is particularly fortunate our (contd.) | ||