There is almost no perceivable space in the bores at idle setting.  I
agree with the suggestion of drilling 3 small holes (one per runner) in
the slide.  I had considered doing that to help during idle.

As for the air leak... During idle, the 2" hole in the Teflon slide for
rotor #1 moves very close to the hole in the frame for the cable.  This
could provide a path for the air to bleed into the #1 rotor causing it
to run lean.  This may account for the higher than normal MAP as well as
a mismatch in air-fuel mixture during idle.  It would become less of an
issue as the throttle is opened, exactly as I am experiencing.  I
suppose I've got it tuned as well as possible, but with this condition,
I don't see how I will ever get it to run well at low MAP.  It shouldn't
be too difficult to install a small seal.  It sure wouldn't hurt
anything.  I could probably stuff a small piece of shop towel around the
shaft for a down-and-dirty test.  If the idle improves I'll know that
I'm on to something.

Mark S.

A seal would be worth a try in that case.
For future use do you have room to make the slide an inch or so longer?

Paul Lamar



Paul,

I guess it is possible (anything is possible), but not really practical.
  Ref. *Marks pics 2009-2010 287.JPG *showing how close to the firewall
it is now.  The other end is up against the oil cooler.  So, what did
you have in mind?

Mark

One inch longer on the fire wall end.

But try the seal first.

Do you have Teflon on both sides of the slide?

That should help seal the top and bottom in case it is leaking
around the edges. Also what is the exact gap at idle?
I can figure out the area.


Paul Lamar