Old 09-28-2011, 06:41 PM
  #1  
markdunlap
Senior Member
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Join Date: Jan 2004
Location: central Illinois
Posts: 459
Default Holley 4150 HP idle air bleed change refresher course.

OK, need a refresher.

If I have throttle blades set with approx. .040" idle slot showing below blades, and my 4 corner idle screws give best idle at only 1/4 turn from full in, am I lean or rich?

Will changing the air idle jet sizes allow adjustment to 1 1/2 turns out on screws and will this be any better idle quality than the 1/4 turm out?

Bigger idle air jet will lean fuel/air mixture?

What else is there to getting better idle quality?

377 SBC with .520 hydraulic roller cam, 750 HP carb, 21 degrees initial and 38 degrees total timing, 7-8" vacuum at idle, 1000 RPM idle in neutral, 800 RPM in gear, 3500 RPM converter.
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