Why aren't surface gap plugs used in 4 stroke engines? You must be the man! You have the right name for this discussion. Where'd that come from?
Surface gap plugs are used in some competition engines, such as F-1, mainly due to combustion chamber design. There just isn't room for the ground electrode in those engines. As for clocking the electrodes, or making sure the gap points towards the cylinder has long been a trick of racers. We set when the heads are off, and sometimes just by marking the plug with a sharpie and checking before we put the coilpak or wire back on. As for my moniker, in my early days of boating, really not too long ago, I would spend a lot of time checking stuff and getting ready for getting on the water, but in my haste and excitement, I would forget to put the bilge plug in. So similiar to the old biplanes, they would yell "Contact" to tell the pilot to energize the ignition, my friend Tim and I would yell "Plugcheck" before heading to the truck to back in. So it kinda seemed fitting, since I've done this several times now.
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