I'm getting ready to change my plugs, wires, cap, rotor. I also plan to run seafoam through the engine. Will the seafoam foul my new plugs? AC Delco iridium btw,

 

Doubt it

 

I don't think it will either, but if you're worried about it just run the seafoam through before you change the plugs.

 

I went ahead and changed the plugs, it will be a couple months before driving it again, we will see what happens.