Auto Parts: sparkplugs, heat of combustion, stroke motor

Question
what is the difference between  cj8 and cj8y sparkplugs? will a cj8 be ok if a cj8y is called for? -gasoline backpack blower

Answer
    The way that Champion numbers break down, they have the same thread and the same depth of thread and they use the same size wrench.  The "Y" on the end means that it has an extended tip.  With a 2-stroke motor (oil mixed with the gas) they nearly always use an extended tip plug.  The extended tip lets the heat of combustion burn the crud off of the electrode.  And 2-strokes have a lot of crud because of the oil.  If it's an emergency, and all you have is the CJ8, go ahead and use it.  It won't hurt anything, but it will foul out more quickly.