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).
Graph comparing the performance of Lodge and K.L.G. spark plugs under various running conditions.
| Identifier | ExFiles\Box 162\1\ img046 | |
| Date | 19th September 1938 | |
| COMPARISON TEST OF LODGE 641 THREE POINT AND K.L.G. FLB 30X PLUGS. TESTS PERFORMED ON CHASSIS 3 B.W. No. 6 CYL. BEING USED THROUGHOUT. LODGE 641 T.P. CURVES SHOWN THUS K.L.G. FLB 30X MAX. VOLTAGE ACROSS POINTS (K.V.) PLUG GAP. PICK-UP SLOW RUNNING HIGH SPEED 12.0 10.0 8.0 6.0 4.0 2.0 0 .020 .025 .030 .035 .040 R.R.J | ||