> Hi Paul,
    > I know you're a proponent of P-porting, but if someone only wanted to
    > create large street ports in a 20B which porting templates should
   be used.
    >
    > Thanks,
    > Don
    >
    >
    > I have no idea what works best because we have not heard from enough
    > people that did it and flew it in an airplane. IMHO it is not
    > cost effective as it is skilled labor intensive but it surely
   won't hurt.
    > Only modest gains are achieved and it must be combined with a proper
    > intake manifold with runners of the right length and diameter.
    > In other words it should be dynoed to tune it for 6500 to 7500 RPM.
    > So far nobody has done that as far as I know.
    >
    > Here is some data and pictures on the subject.
    >
    >
    > Paul Lamar ...No rotor no motor.

   Bruce Turrentine put a mild street port on our 20B when he built it up.
   If we ever get time to work on the airplane.....

   Chris Cosman


Don,
What I did on my 20b was to open up the smaller primaries so they
matched the larger secondaries.  I did this since I am using a single
throat TB and not the progressive 3-barrel TB and dual plane
manifold that it came with.  It still idles fairly well down to around
600-700 rpm.  I've seen as high as 6,500 rpm on static runups.  But
that's with a constant speed prop.

Mark St.



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