Ok, I ran across something I’ve never encountered - or heard about before. Looking at a car with a 440 in it. PO tells me he had a problem with it “blowing plugs” initially. By blowing he says that a couple times it blew the centers out of the plug, electrode and porcelain??? Not sure if it was same cylinder each time. He claims the plugs would run fine for a bit and then one would blow - as described... He also says the he switched to NGK plugs and it solved the problem. Supposedly a fairly normal 10 or 11:1 compression motor, nothing out of the ordinary. I’ve never heard of this before and honestly struggle seeing it? Thoughts??