Tom,  originally I investigated Racing Beats P ports.  A couple
of
points that I want to bring  up but if they sound wrong to anyone

else,

  don't hesitate to set the record straight.   These ports are
very
large and they are timed for an engine turning very high rpm.
Jim
Mederer told me they would not perform at 6000 rpm. They will not
perform at 7500 rpm either. I believe he said 10,000rpm and up.
Another point,  these are just inserts.  Not throttle bodies.
There

is

no way using the RB housings to have the butterfly right at the
port.
This is important for throttle response and idle.   Lastly,  the
ports
are bored perpendicular to the housing. Consequently, they are
angled
upward.  This makes it even  harder to get adequate intake runner
length.   At our relatively slow turning engines the runners need
to

be

around 22 inches in length for 6000 rpm. For these reasons (and
some
others) I decided to roll my own.  But I got a lot of expert help
and
advice all along the way.  At this point, I think we have the
timing,
size and shape of the ports optimized for our application.
Within
weeks we will have a nice, air worthy throttle body.  Boring the
housing is not hard to do,  but a local machinist is going to set
up

to

do a precision job at a very reasonable rate.   All this is
coming
together right now.  It a few months you will be able to send in
your
housings and get them back p ported with throttle body installed.
Jerry

Jerry,

Do you have a "concept" sketch of what your final intake system
might

look like?  I've been following this closely, trying to figure out
where you
are heading with this.  My impression so far is dual throttle bodies
placed
in close proximity to the rotors, but then you mention 22" runners.
Where
do the injectors, air intake, and runners all fit in?

Bob Lemings

It will look almost identical to this Power Sport P-port manifold
that

Allan Tolle

used in 1995 to go 238 MPH in the Sun 100 race.

Paul Lamar

Jerry, I find it hard to believe that smaller ports will give you more
than 240 HP at 6000 RPM that you would get with the monster Leman
ports.  We should dyno two engines back to back to find out for sure.
Notice that the BSFC is lowest on the Leman engine at about 6200 RPM.

Hans "I-can't-believe-I'm-disagreeing-with-Jim-Mederer" Conser

 
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