The valve openings in the head are shown here. The inside surface
of each valve has been polished somewhat to remove burrs and
increase engine efficiency. Performance seekers will completely
smooth these openings through polishing to increase the efficiency
of the valves.To install hardened intake and exhaust valve seats, a portion of the
head surface must be removed so that the deeper valve seats can be
installed flush with the head surface. For this procedure, Herman uses a
valve guide seat machine for this machining. The bore is measured to be
.005 inches smaller in diameter than the new valve seat to ensure the
seat remains in place after it is pressed in the head.
A guide is then placed inside the exhaust or intake valve opening in
the head to center the bit. After ensuring the bit is in the center of the
opening, it is slowly lowered into the head. Herman removes only a little
of the surface of the head with each pass, and frequently checks the
depth he’s removed from the head surface so that he does not remove
too much of the head. Once the amount of head surface removed
matches the depth of the new valve seat, the area is ready for the seat to
be pressed in with a punch. Lock-Tight is also applied to the seats at this
point as an extra measure to ensure they remain in place. Once the seat
is installed, its surface is machined smooth to match the valve passage
way, thus creating less turbulence as the valves open and close during
the air intake and exhaust sequence and helping the engine run more
efficiently.
The right rods
In this engine rebuild project, the original rods were going to be