Jerry Hey wrote:

Paul,  the p port throttle body is a bit closer to physical reality
today.  The butterfly has been installed.  It is brass and the shaft is
stainless steel.  The shaft was slit and the plate slipped in.  It is
retained by two bolts.   The shaft rides in ball bearings.  It is nice
and smooth.  In the photos it is slipped into a 12A housing.  The red
portion is to be trimmed away.  I was going to do this by hand but have
been convinced that it can be done in the mill with a rotary table.
That will take place about a week from now.  The little tube next to
the throttle arm is a pressure tap for
Tracy's controller.  The butterfly shaft is too long.  It will be
trimmed eventually.

This is a prototype and we can change anything we want in an effort to
make it better.  No  problem.  I hope everyone will study it with a
critical eye and help me get in right.

I should mention that the bore is 1.5" but it can be larger should that
prove beneficial.   According to Rolf's calculations it is very good
for the 2:17 engines (up to 7000 rpm) so I am going to leave it as is
until we can test it and get real performance numbers.

Question:  is a throttle stop to prevent total closure sufficient for
idle?

  Original design:   Paul Lamar
Sizing and timing: Rolf  Pfeiffer
Machining: Bob Dunfee
Pest:   Jerry Hey

Yes I would say so on the throttle stop.

Paul Lamar
 
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