Outboard Motor Coils

[iNCH]

Surface discharge plugs, what's the point?
Er, there isn't one, and that's the advantage. Not having 
a pointy bit sticking out into the combustion chamber, 
there is a very short path for the heat to be conducted 
away into the cylinder head. So, I would say that these 
plugs would be ideal in hot situations.
One problem running them in a two valve would be the 
positioning of the plug, the flame path would be 
increased, requiring more ignition advance.