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spark plug gap



put MSD wires and AC/Delco Platinum plugs on my 96 LT4. It now has a very slight rough idle.

GM specs say a .05 gap on the plugs. I've read that someone increased the gap to .06 to .075 to cure this.

Will this help? If this does help, is the .06 to .075 setting correct? Does this have an effect on the "non-idling" performance?



Question: What was your idle like before the switch?

I doubt very seriously if the technology of the wires and plugs are the problem; not for an idle situation, anyway. I suggest you think back over your installation. Much tugging on the plug wires, trying to sneak them into position? Are you absolutely certain that all wires are securely popped down on each plug. I have found that it is very easy to not make good contact with some plugs that are in ugly positions. I suggest you go back and take one more look at each and every plug to wire fit. Did it "pop" on securely?

Also, go back and take a resistance measurement of each plug wire. If you had no idling problems with your old wires, I would be interested in knowing how the resistance compares, wire-for-wire. Write back and let us know what you find.

Ted Valley

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