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Had To Gap Autolite 66 Copper Plugs


Well-Known Member
Local time
6:31 PM
Nov 29, 2014
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La Paz, B.C.S., Mexico
The 8 Autolite plugs I purchased at AutoZone Mexico were made in China and none of them were gapped at .035", half were about .020" and the other half over .040".

I remember most every spark plug I ever purchased seemed like it was already pre-gapped at .035" (since the 1970's). Of course, like today, I checked the gap back then before installation. I see the round gap tool I purchased some years ago was made in China also.

And I am tempted to keep the worn Autolite plugs I removed, just in case.
I bought champion plugs last week and they were dead on.
Its weird i order the same part # autolites and sometimes i get some cheaper ones with black phosphate-looking finish and sometimes get some with good chrome/nickel plating that stand up to solvents and ultrasonic cleaning really well. Its a toss up. But I usually pay like $1.20 each from rockauto so no big deal.
I believe the MFG gaps their plugs at the most commonly used setting for their application.

I want to say gm uses a .040 gap for the same plugs.
...of course if the box gets dropped and lands on the electrode end, there goes you gap.
Always check new plugs for the proper gap....always It doesnt matter what brand