Re: spark plugs
The Q has an inductor in it that functions sort of like a resistor in a resistor plug. <br />What it does for you is lessen radio interference from the ignition system. Without the Q series plug, your VHF radio and cell phone will likely be noisey. I'm not sure if fishfinders react to the interference or not.<br />For the most part, all modern outboards use some sort of radio noise suppressing plug.