The Stovebolt Site Forums The Shop Area The Electrical Bay which coil is better

I have three coil for my gmc 248 they all work, but I like to use the one that gives me just that much more power to the spark.. how can I do this

I'll take a shot but am not sure I'm right. Without a tester to measure the high voltage pluse from the secondary or output side it might just be a guessing game. You could take an ohmmeter and measure the primary resistance and the the secondary resistance. The coil that gives the largest ratio of resistance between the primary and secondary should give the "hotest spark".

The output voltage of a coil is determined by the spark plug gap, and the condition of the center electrode. A spark fires better off a square corner than a rounded surface, so keep the electrode filed flat and properly gapped.

A clean plug with the right gap will fire at around 8,000-10,000 volts, and a standard coil will develop 20,000 volts or more on open circuit. If the coil wire will jump a 1/2" gap to ground as the engine is cranked, you've got plenty of voltage to run the engine under any normal operating conditions. High performance- - - -that's a different can of worms. A high-performance coil for street use is an exercise in futility.
Jerry