butterfly whistle, and cure

[Bruce Plecan]

 Ref:   CCC Q-Jet Carb....  (Computer Controled Carb.)

 The whistle was getting to really be annoying.
 Several people had asked if there was a roots charger, or gear drive.
 Got the trick prom from GM, set the timing every where, and no change.
 SO:

 Pulled carb.
 Looked at butterflies to bore clearance.
 Looked at butterfly to transfer port relationship.
 Looked in manifold,
 The only thing the least bit off was that the butterflies uncovered the
 transfer slot maybe .045 instead of the .030 that I like.
 With nothing else, to even look at, I figured WTF, and got an .093 drill
out
 and punched a hole in each primary butterfly by the transfer slot.  Backed
 out the speed screw exactly 1 turn, and reinstalled the carb..
 Warmed up the engine, and started kicking the choke off a little early.
Had
 to start adding speed screw, to keep it from a "dead" stall.
 When warm wound up being 1 turn back in, Hmmmmmmm.
 In working the mixture screw wound up two full turns out.
 Now the funny part is that I had drilled the idle discharge holes, so that
 at 3.5 turns (idle mix screw setting, was mix correct), and in this
 installation they only wanted to be at 1.5 turns out.
 Being a CCC Carb. really doesn't make the screws that meaningful, was just
 going by the reported M/C dwell to set em anyway.
 The is now no trace of a whistle.
 OK, sometimes ya just gotta go, well it works, and close the hood
Grumpy

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