The deck is drilled through at an angle that allows a screw to be put in that preloads against the casting inside. The head of the screw is then cut off, and the head surfaced. This provides some deck reinforcement, at least theoretically. I have a book or article somewhere that shows that done below the bottom of each chamber.Originally posted by INTERCOOLER:
I hear the term passed around of "pinning" the heads to hold a head gasket better. Anyone know how this is done?