Spark plugs gap

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Oct 27, 2023 | 08:37 AM

captain vette

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From: Canada

Spark plugs gap

I’ll swap the plugs on my new to me 2003 in the winter, I’m confuse about the right gap the one I buy are pre gap at .040 although my owner manual says they should be gapped at .060

Oct 27, 2023 | 12:16 PM

bookyoh

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I believe if you buy the AC Delco iridium plugs you will find they are pre-gapped at 0.060" which is the correct gap for our C5's.

Oct 27, 2023 | 12:27 PM

captain vette

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From: Canada

Quote:

Originally Posted by bookyoh

I believe if you buy the AC Delco iridium plugs you will find they are pre-gapped at 0.060" which is the correct gap for our C5's.

not sure

Last edited by captain vette; Oct 27, 2023 at 12:28 PM. Reason: Errors

Oct 27, 2023 | 12:32 PM

jamieo

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From: Tollesboro Kentucky

The .060 gap was for platinum plugs.The .040 gap is for the iridium plugs

Oct 27, 2023 | 01:06 PM

bookyoh

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From: Cincinnati Ohio

Quote:

Originally Posted by jamieo

The .060 gap was for platinum plugs.The .040 gap is for the iridium plugs

Thanks for the correction. I changed my plugs a number of years ago and looking at one of my old OEM 41-952’s, they were gapped at 060”. I believe there was a TSB that changed the gap to 0.040”.

Anyway, the 41-162’s come pre-gapped and you are not supposed to adjust them.

Oct 27, 2023 | 01:11 PM

jamieo

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From: Tollesboro Kentucky

I usually check mine to be sure they are in spec.Just be sure and get them from a good source.A lot of fakes floating around.If they are $20 a set,you can be assured they aren't legit.

Oct 27, 2023 | 01:34 PM

grinder11

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Quote:

Originally Posted by bookyoh

I'm certain you're correct on the plug gap change from .060" to .040". .060" is too large. As for pre-gapped plugs, I never install them without checking the gap first myself. Because around 10 years ago I got a new set of 8 plugs, and 1 of the 8 had the ground strap slammed against the electrode!! After that, I always double check the gap...

Oct 28, 2023 | 07:00 AM

jdmvette

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From: Bugs Bunny should'a made a left turn here

Quote:

Originally Posted by jamieo

I usually check mine to be sure they are in spec.Just be sure and get them from a good source.A lot of fakes floating around.If they are $20 a set,you can be assured they aren't legit.

Yes I was scammed with a fake set of NGKs on Amazon; ignitors gone on all 6 in a very short time. Bought a legit set locally at O'Reilly's which should last a decade or longer