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Spark Plug

260 Views 8 Replies 5 Participants Last post by  Karadjgne
Has anyone seen this ? Went to change my spark plugs and number one had this on the spark plug. I've never seen a plug half shaded like this.


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what do you have them gapped at? what kind of ignition system do you have?
Doesn’t look bad, we’re you running an additive maybe?
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Hi, no additives Jasper engine with about 1500 miles on it. Started running rough so I decided to check the plugs. It is a 87 el camino with a 305 (Calif special) stock ingnition, stock carb.
Oh, sorry gap is 35
From what I've read on this site the spark plug gap should be .045"and that the underhood sticker for ignition specs is wrong when it reads .035 in.
The California car could be different.
I have it bookmarked as Gap matters 0.045 FYI.
I will try that. Looking at the engine with all that smog equip seems you need to be a contortionist to get at these plugs. And small hands wouldn't hurt. 😂
Did some research , your right ! .045 is the way to go. Thanks
If the cathode isn't squared to the pin, if it leans to one side or is off center enough, that'll be the side that constantly sparks, so that's where combustion will start which could cause that shading.
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