Years ago, there was a TV ad that would run late at night and during wrestling for a "wonder spark booster". They had a '50 Packard straight 8 with the hood removed (easy to do, it opened from either side and lifted off if you released both latches) and attached this "spark booster" between the distributer cap and the coil wire. Then, with the engine idling, they removed 7 plug wires one at a time and the engine kept running. Well, Packards were luxury cars that had such a heavy flywheel and crank to make them run very smoothly (the only way you could tell a Packard straight 8 was still running at idle was to look at the oil pressure gauge) that they would do that anyway. Sometime later, one of the scam debunkers that were popular on telly at the time cut one open and there was nothing but a 1/2 inch spark gap inside. It "worked" by keeping the spark from the plugs until the coil output peaked. Poor people had been doing the same thing for years, cutting a plug wire and taping it back together with a gap to help keep the plug from fouling from a worn valve guide or bad ring.
