[6pack] RE: Spark plug gap with electronic ignition

[Tomislav Marincic]

Actually, unless you open the gap up, the voltage will be the same as it was with your old coil. It will be exactly the voltage required to overcome the resistance of the wires, distributor, plugs, and air gap, and not a millivolt more. The "40,000" is a reference to the coil's capability.

Try .045" to start. Drive it like that for a while, then pop the cover on your distributor and see how the cap and rotor are handling the increased voltage. Look for signs of arcing, carbon trails, pitting on the copper, etc. I've never gone up from .045, because the rest of my system can't handle it for long, but that doesn't mean you can't. RPM, the condition of the engine, the CR, the A/F mixture, the design of the plug, and probably many other things all affect the resistance of a given spark plug gap.

Also be aware that your plug wires must be in perfect condition. As the resistance at the plug will be larger, the spark will be that much more eager to find an alternative place to go to ground. Spray your plug wires with a water mister in a darkened garage with the engine running and look for sparks.

Cheers, Tom