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).
Misfire troubles with Delco ignition coils on the Wraith model during hot weather.
| Identifier | ExFiles\Box 164\5\ img391 | |
| Date | 24th August 1938 | |
| 6017 To By.{R.W. Bailey - Chief Engineer} c. to Da.{Bernard Day - Chassis Design} c. to By/RD. c. to Mx.{John H Maddocks - Chief Proving Officer} Rm{William Robotham - Chief Engineer}/Wym.{G. Harold Whyman - Experimental Manager}9/JH.24.8.38. WRAITH IGNITION SYSTEM - COILS. During the recent spell of hot weather we have run into misfire troubles with the Delco coil, due to the high temperatures reached after a period of continuous running. Although we have been running on Delco coils for the last 9 months, this trouble has only just shewn itself. Delco coils were fitted originally because of the excellent start they gave us on the Wraith car under extreme cold conditions, i.e. 8°F.{Mr Friese} but it is now evident that they will not stand hot conditions. From the attached report it will be seen that the Lucas Sports coil, and the R.R. coil are satisfactory under hot conditions, and now give us a good start cold (improved carburation and choke control is no doubt mainly responsible for this) and we suggest that for present production we fit the R.R. coil, and continue experiments with the Lucas and Delco. It should be remembered however that we have had failures with R.R. coils, and further development work is still necessary to make them 100% efficient and reliable. Rm{William Robotham - Chief Engineer}/Wym.{G. Harold Whyman - Experimental Manager} | ||