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).
Adjustments to the distributor and sparking plug gaps for the 20/25 HP ignition system.
| Identifier | ExFiles\Box 54\5\ Scan337 | |
| Date | 4th November 1930 | |
| X5680 EFC. {E. Fowler Clarke - Electrical Engineer} c. By {R.W. Bailey - Chief Engineer} /RD. Ey6/C4.11.30. X.5680. 20/25 HP. IGNITION SYSTEM. X.5690. X.8712. It would appear that our gap as provided in the distributor from the rotating finger to the aluminium casting is somewhat on the low side with the high compression engine. At the moment we have reduced the sparking plug gap from .025 to .020, but it looks as if we should have some slightly increased margin over this by increasing the safety gap. The point we have in mind is whether the coil is capable of withstanding an increased stress, which would result from increasing the gap or whether we must depend solely upon maintaining the reduced sparking plug gap as our only protection against misfiring. RV. | ||