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).
Effects of adding a high-tension coil to an ignition system to reduce sparking.
| Identifier | ExFiles\Box 34\1\ Scan031 | |
| Date | 26th April 1917 | |
| E.B.R. (G.D's) M.{Mr Moon / Mr Moore} of D.{John DeLooze - Company Secretary} 408. 26-4-17.) Bm. 2/156/13. EFC1/AT101218. Contd. -5- A coil with about a dozen turns of high tension wire insulat-ed{J. L. Edwards} at one end and connected to the high tension terminal of th ignition coil, has a definite and distinct effect in reducing sparking at the primary points. We can, by suitably proportioing the primary and secondary capacities, get perfectly regula sparking at all speeds on the six air gaps, with practically no sign whatever of any flashing at the primary points. The only detrimental effect which is likely to be apparent, through the additional connection of a small high tension capacity, may be due to the fact that the secondary spark is rendered more of the nature of a higher frequency oscillation and might not be quite so good at starting the engine when cold, also, the actual voltage available is somewhat decreased although, of course, the amplitude of the oscillat on is increased. This however, is a point that can be tested out experimentally in actual running on the road. EFC. | ||