I agree with you about dirt track guys being able to
transform stock chevy heads into works of art. My point
dealt more with experience in porting roadster heads. I
can hear it now: "Pass me the die grinder Vern. Well
gaaawleeee! My mouse motor don't have no oil gallery
there. You got an extra head by any chance?" The
average Joe with a Dremel can do a good job polishing
and gasket matching a head, but making power by porting
the head is more complicated than hogging out the intake
and exhaust runners. That process should be left to
someone who knows what works and what doesn't. I've
seen a few home port jobs done on U20 heads. It's
amazing how bad they were screwed up. Some examples
include the septum between the valves were ground away,
combustion chambers "opened up" to lower compression
using a chunk of concrete (aparently) as a tool, and
valve stems ground down untill the heads snap off. What
is even more amazing is that they placed these mangled
heads on their precious cars. (probably with great pride)
I have nothing against the home mechanic and "alternate
engineering", but I feel some things should be left to
an expert.
Andy
> Andy,
> IMHO, you might want to rethink your statement.
> Porting is an ART. I have used some very good "home grown" port jobs, and we
> actually lost performance when we went to a "specialist" port job. You are
> correct in your thinking on a good valve job. A mild port job may give
>better
> low-end performance, while a total Port and Polish most likely will be
>"tuned"
> to a much higher RPM range.
> Phil,
> 69 2000 hillbilly dirt-track motor builder and proud of it
>
> Philip Erickson
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