I talked to a guy that used to engineer for Champion (one of my older brothers contacts). He said that the bursting insulator is not an unknown phenomenon. He told me that a damaged boot on the plug wires can cause this to happen because the arcing causes the plug to heat up way beyond normal limits & POOF the electrode expands bursting the insulator.
Solution:
Replace plug wires AND plugs at the SAME TIME. Set plug gaps to less than factory spec, specifically he suggests 0.046 to 0.050 (err on the lower side of the range). He said the narrower gap will cause things to run a little cooler, thus helping to prevent the excessive heat buildup.
Based on the information I relayed to him, he also suggests double checking the resistance in the coil pack. If its outa spec the voltages can DOUBLE in order to compensate & that will also cause a quick build up of heat in the internal workings of a plug. (sounds like this ties in to the arcing thing in the first paragraph)
Ken, we're gonna kick this in the butt dude!!
