On the intake face of each head is a "half moon" (upside down smiley face) slot around the "heat hole". I have never heard a logical explanation for the purpose of the "half moon" (upside down smiley face) slot.
Can someone shed some light on this subject for an old fart.
Can it be pugged, should it be plugged? Ifthose of you have plugged it, why did you chose to do so, how did you do it and was it successful?
The heat hole, I have heard various versions of plugging those, but none seem...
General Cylinder Head Question
