Spark Plugs

[Hank70SS]

Some do jump up to .060 gap with HEI but more common is .045. The larger the gap the more resistance in the circuit. The more resistance the more chance that high voltage is going to find another path to ground. Like maybe punching a hole through the plug wire insulation and crossing to another plug wire or to the block. Maybe even causing carbon tracking in the cap. .060 will work but everything else better be up to the task. That's why newer cars have individual coils right near the plug, less components to brake down while pushing that high voltage around.

What plugs are you running now? There is nothing wrong with AC or even Autolite, I know Ford. I guess I'm not a big fan of $10 a piece plugs. These cars been running pretty strong for over 40 years with standard resistor plugs.