It takes some effort to get anything to contact a piston in a stock 225. Even large cams & o/s valves, the piston is soooo far down in the hole,....the tip on the spark plug'd have to be 13/16" longer to get close, lol! By that time You'd realize the intake valve has collided with the plug 1st...., even with a -0- deck piston the ground electrode on a stock plug is about 5/8" from the deck surface of an unmilled head(on the plug's centerline), so no worries there!!:thumbsup:
