Paul Lamar

I believe Paul's recommendation for runner length for a 6000 rpm engine
is 22 inches.   As the RPM goes  up, the runners get shorter.   I don't
know how critical this is but getting as close as possible  to the
ideal is our goal.   The only reason we  have the insert set in
parallel is to gain runner length.  It does not effect performance.
What does effect performance is port location, size and perhaps  shape.

  Location and size are just another way of saying timing.   If you
increase the size of the port you will effect either the opening or
closing events and probably both.  Same is true if you change its
location.   In our case we have minimized exhaust overlap while
providing a port that is sufficient to deliver all the charge needed
to run at  8000 rpm.  I forget at the moment where our  port reaches
max flow, but it is far below 10,000.  That is where RB's is just
kicking in.

I don't know for the 12A but I do know that there are some very
powerful p ported 12As out there.

 BTW,  for those who want to experiment,  I will be glad to supply the
throttle bodies.  You can bore them to any size you want and place them
anywhere in the housing  you like.  I will be very interested in
reading the reports.      Jerry

 Thanks Paul and Jerry,
I will soon take you up on that Jerry, I've been talking to Butch on the
benefits and possible leakage issues.

We are helping each other on the aluminium end housings ( he's the brains)
and PP would be an enormous benefit in eliminating design and feed of the
side ports.
I guess that's why Richard Sohn is using them.

George (down under)

 
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