Sxrxrnr, no misfiring, the car runs great. When I drive the car, which isn't very often, I generally blow it out pretty good. The only reason I am even looking at the plugs now is because I am doing some other maintenance, like changing header gaskets and such. Yes, all the plugs are black, some a little more than others.

I am considering running a hotter plug, any recommendations? Is the next hotter plug the RJ18YC???