Spark plugs, which ones?
Thread Starter
Cruising
Joined: Apr 2008
Posts: 13
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From: San Rafael Ca
Spark plugs, which ones?
I have a '99 vert. 6 speed, stock motor, 50,000 miles
I have 3 manuals for the car, all three say to use AC 41-931 plugs and to gap at .060.
Went to NAPA auto parts, part # AC 41-931 comes up in their computer as an electrical connector?
Looking up the car by year shows a few diff. spark plugs but they all say gap is either .050 or .040.
What gives, did AC change the part #?
What should I use for plugs?
I have 3 manuals for the car, all three say to use AC 41-931 plugs and to gap at .060.
Went to NAPA auto parts, part # AC 41-931 comes up in their computer as an electrical connector?
Looking up the car by year shows a few diff. spark plugs but they all say gap is either .050 or .040.
What gives, did AC change the part #?
What should I use for plugs?
Race Director
Joined: Aug 2003
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From: Lake Mary Florida
Team Owner
Joined: Jul 2004
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From: Danville Virginia
Ac Delco iridiums and the GM performance red wires are a great combo. Do not re-gap these plugs and don't forget the anti-seize on the threads and some Di-Electric grease on the boots for easy removal next change. 
Chuck
Chuck
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Another one here with NGK-55s and GMPP Red plug wires
Very happy with the combinations.
Top tip, if you change the plugs assume you'll need to change the wires. Youre bound to break a few getting them out.
Very happy with the combinations.
Top tip, if you change the plugs assume you'll need to change the wires. Youre bound to break a few getting them out.
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From: Titusville FL
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This is the combo I went with (got them from Gene at gmpartshouse.com). Made a nice difference in how the car ran.
