So I picked up some 438 - RC12ECC copper champion plugs at auto zone when I was there, but can't seem to find my feeler gauges. Does anyone know if they are pre-gapped to .035?

 

Never trust the factory gap setting. Aways gap them yourself.

 

yeah usually they are pretty close but you never know, i remember when my buddy was doing his he was wondering why it ran worse after, well we pulled them all out and they all were perfect except one was wayyy of, it was like .050 lol

 

Agreed. It only takes a minute and everybody installing plugs needs to have a gauge for this.

These plugs will be in your engine for a long time. Get em off to a good start by verifying .035 gap.

 

It costs a dollar for a plug gapper at the auto parts store. I say invest and always check yourself.

 

Mine were pre gapped but I had the guy at autozone verify the gap on all the plugs right in front of me before paying for them. But like another member mentioned but your own gap gauge so you can check or adjust your plugs in the future.

 

I checked the gap and they were all ok, just about .035

I just swapped them out, and the NGK's that were installed all had gaps ranging from .07 to .09. Is it normal for the plugs to change that much while in the engine, or did the PO really mess things up?

 

Swamiji says he does not know, you tell him nothing and yet you want answers??

 

What does that even mean?

 

You will never know for sure what the gap was when the NGK's were installed, but yes, the gap typically gets bigger as plugs wear. The center and side electrode erode and the gap increases.

I've seen plugs that had the center electrode eroded below the surface of the porcelain and the side electrode nearly gone.