Wellll, I finally received my new head and it tis a thing of beauty. It has
a better casting than any head that I have seen or worked on yet. No major
flaws/air pockets/casting flash in the ports and the combustion chamber is
quite smooth which is surprising.
Of course I had to improve things and opened up the intake ports which snake
down in the port on stock heads and I probably gained another 1/4" of flow.
I also opened up the casting around the valve guides. I port matched the
head to the intake manifold.
The exhaust ports remain the same size except I radiused the edges so carbon
doesn't collect as easily and I also sanded and polished the exhaust ports
in futherance of reducing deposits. I left them the same size because you
shouldn't match the exhaust port to the header as the mismatch in sizes
promotes anti-reversion which is important for exhaust scavenging.
I also smoothed out the combustion chambers and polished them smooth to
reduce carbon deposits and smoothed all the sharp edges so I don't get
pre-ignition or run on.
I'm planning for the machine shop to helicoil the rocker stud threads and
the thermostat threads and install removable oil passage plugs which the
head didn't come with.
Goes into the shop on Monday and I should have my car up and running by
Saturday afternoon - finally.
Mike
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