Holley 4150 HP idle air bleed change refresher course.
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Join Date: Jan 2004
Location: central Illinois
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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.
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.