Originally Posted by fairracing31
Hmmm.... Thier might be a problem with the head thier that you are not getting a good seal between the plug and the head...It is a good ideal to use some thread anti-seize on the plug
A pic of the head with the plug out may help to see what's going on
I'm kinda agreeing with this. Nothing should be a-blowin' past the plug. I would get a new head gasket and then take the head off (spark pug first), and carefully check the plug mating surface.
Should not matter what the oil mix ratio is.