Testing a method to increase spark current

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from that first link you gave:

A small peaking capacitor mounted next to the plug can be added to a conventional ignition system as an aftermarket application. This will deliver more energy during the initial breakdown phase of the discharge and a larger spark formation. This increases ignition system performance for a small increase in cost.

At low load, however, when more potent ignition is needed to ignite the air/fuel mixture, the system shows little improvement, because it produces a low breakdown voltage. At high load, when enhanced ignition is not usually required, the capacitor is charged to high voltage and delivers significant unnecessary energy. In addition, the peaking capacitor causes rapid electrode wear, due to the high currents passing through a stationary arc.
 
I disagree with the previous statements concerning low and high load needs. I agree that plasma spark may not produce great power increases but every little improvement helps add to a good package.
Retesting today with 6 capacitors in series for a equivalent capacitance of 113pf, and a spark gap of 1.8mm (to simulate being inside the engine), the spark would only happen from 1300 to 9300 RPM. So I am ordering smaller capacitors to test equivalent values of 73pf and 50pf to see what happens.
 
I disagree with the previous statements concerning low and high load needs. I agree that plasma spark may not produce great power increases but every little improvement helps add to a good package.
Retesting today with 6 capacitors in series for a equivalent capacitance of 113pf, and a spark gap of 1.8mm (to simulate being inside the engine), the spark would only happen from 1300 to 9300 RPM. So I am ordering smaller capacitors to test equivalent values of 73pf and 50pf to see what happens.

I was thinking the same thing. And what did they mean by too much energy discharge at higher loads(rpm's?)? I cant imagine that there would be too much discharge at any point.
 
"At low load, however, when more potent ignition is needed to ignite the air/fuel mixture, the system shows little improvement, because it produces a low breakdown voltage. At high load, when enhanced ignition is not usually required, the capacitor is charged to high voltage and delivers significant unnecessary energy."

yeah low load is not that important because that is when you are off the throttle or just idling but it doesn't change the breakdown voltage. That voltage needed to spark the gap is more dependent on the compression which is more when you are on the gas within the expansion chambers powerband. The voltage from the high voltage coil is low at real low and real high RPM, not anything dependent on the load.
And I don't see why they think a fatter spark is inconsequential at high load. Possibly with a denser mixture it takes less spark power to ignite it, but still the speed of the flame front increases or decreases speed with the strength of the spark. Flame front speed needs to be as fast as possible when performance is important. Of course then that may require retarding the ignition to have the peak combustion pressure happen at the same time of each engine cycle.
 
I had to keep lowering the capacitance trying to find what works. Even down to 50pf it still lowered the spark voltage too low to run my Suzuki 100 although it seemed to work on my bench tester with the spark gap set at 1.8mm
 
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