Autolite Spark Plugs
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Instructor
Joined: Nov 2010
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From: St Petersburg, FL
Autolite Spark Plugs
Ok, I have a stock 1992 LT1 Corvette. I installed Autolite Copper Core Resistor plugs and gapped them to .035 because that is what the Autolite website said for my application. I am still working on the car and have not fired it up yet. I noticed that the factory plugs are gapped at .050.
My question is, is the .035 gapping for the Autolites wrong? If so, what should I gap them to?
Thanks!
My question is, is the .035 gapping for the Autolites wrong? If so, what should I gap them to?
Thanks!
Drifting
Joined: Dec 2007
Posts: 1,647
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From: Argillite KY
For performance applications I believe that .010 less than the factory recommendation is fine. Remember, the factory establishes the gap based on available voltage, emissions longevity requirements, mileage and performance. For pure performance applications the smaller gap is better. Although less of the mixture is exposed to the spark the spark is hotter without needing a different heat range plug. That's a good thing. I'd go with .040.
Burning Brakes
Joined: Nov 2008
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From: Naples Campania
If your fuel is fully atomized, a smaller gap is fine. It will make a fatter, hotter spark. Less gap = less resistance. less resistance = more amperage. more amperage = bigger boom.
Thread Starter
Instructor
Joined: Nov 2010
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From: St Petersburg, FL
When saying .050, I was referring to the GM sticker under the hood.
I did decide to keep the plugs at .035. Didn't feel like pulling all the plugs just to re-gap to .040.
Thanks for your help guys!
I did decide to keep the plugs at .035. Didn't feel like pulling all the plugs just to re-gap to .040.
Thanks for your help guys!
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From: Maryville Tn
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I'm running a set of Autolite 606's (copper core) in my '93. Can't remember what I gapped them at, but I have no problems with it running or starting.
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From: Database Error Indiana
Thread Starter
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From: St Petersburg, FL
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Burning Brakes
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From: Crystal Springs MS
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From: St Petersburg, FL
What's interesting is that on Autolite's website they list the 106's for the LT1 from 1992-1996, but list the gap as .035 for 1992 and the gap as .050 for 1993-1996.
As far as I know, 1992-1996 LT1's were identical.???
As far as I know, 1992-1996 LT1's were identical.???
