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).
Performance comparison and recommendation of various ignition coils for the Wraith model.
| Identifier | ExFiles\Box 164\5\ img396 | |
| Date | 26th August 1938 | |
| -2- (6) The Lucas coil, although not having the output of the 20,000 turn R.R. coil, gives an equal performance under all conditions. Up to date we have had no failures on this coil. 6 more coils are being obtained, in order to gain running experience. (7) The standard P.III coil to D.75260 gives a good performance with respect to output and running temperature, but this is at the expense of current at break and probably cold starting. Further tests are being carried out to verify this. The rather high value of the current at break may appreciably shorten the life of the contact levers. (8) The Runbaken oil immersed coil misfires at peak temperature. At the moment we are not in a position to recommend any coil for standardisation on the Wraith. However, as the 20,000 turn coil gives a fairly good performance and is an R.R. product, we prefer to use this for the Wraith, until we have a coil, which can prove itself reliable under all road conditions. Rm{William Robotham - Chief Engineer}/RC.{R. Childs} | ||