How often do you change them? It occurred to me that I am pretty much the one who maintains my Z. I do my own oil changes and various lubrication on suspension bits etc.
I'm just shy of 20k miles and I have never changed out the plugs. It has been to the track 3 times. Other than that, normal to spirited driving. Not a whole hell of a lot of highway miles. I've got no misfires, hard starts or anything like that.
So when should the plugs get changed? Which plugs are best?