Sparkplug insulator migration?

[Brent]

Whats wrong with this picture? One of my sparkplugs has the electrode/insulator assembly pushed out of position by 1/2 inch so that my gap was set at 3/4 of an inch (the electrode is up inside the threaded portion of the plug). It appears to have been like that for some time. It idles a little smoother now but it doesn't seem to have affected performance much, go figure. So much for being precise when gapping plugs. Anybody seen this before?

[Dave]

wow, that's pretty funky Brent! I've never seen anything like it before, though I have seen a broken electrode on a spark plug before, when I started to have problems with my engine at Willow Springs International Raceway out in California last month. Not a good feeling to pull a plug and see half the electrode missing. Ugh...buy hey, at least it seems like you've gotten away with this mysterious over gapping :)