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Old 02-11-2018, 12:36 PM   #23
Purdy Swoft
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Join Date: May 2010
Location: Alabama
Posts: 6,750
Default Re: Replacement Ignition Coil

Originally Posted by 40 Deluxe View Post
Answer: It depends!......Depends on how much voltage is needed to jump the plug gap. If only 5,000 volts will fire the plug, that is all the coil will put out. Even if you have a double super whammy "40,000 volt" coil it will still only build up secondary voltage to the point where the spark is strong enough to jump the plug gap, which will never reach 40,000 volts on a Model A, or any stock engine (unless you have totally burned out plug electrodes or open wires, etc.). An ultra high compression or supercharged engine running at wide open throttle may need this much voltage capability, though.
To test coil output, try a "Lisle #20700 Spark Tester". Or, go to a shop with a scope, hook it up and pull a plug wire off and watch the screen.
If this was really the case, no matter what coil or distributor that was used would increase the spark . This is really no so !!! I use a gap of .035 - thats thirty five thousants at the spark plugs . Running at idle speed is not an extra strain on the coil . Idle speed doesn't require extra voltage to jump the .035 gap at the spark plugs. If my Flame thrower coil doesn't increase the spark . Why would the idle rpm increase to the point that I had to readjust the idle speed . I have had similiar results with other performance coils like the 30.000 volt bee hive coils . These coils give performance that a person that has actually used one can't deny .
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