Setting idle speed

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Turn the mixture screws out 1/4 turn. If that makes it worse, turn the mixture 1/2 turn in from there. A vacuum gauge monitoring manifold vacuum would be helpful. Chuck

 
Turn the mixture screws out 1/4 turn. If that makes it worse, turn the mixture 1/2 turn in from there. A vacuum gauge monitoring manifold vacuum would be helpful. Chuck
Will do tomorrow night. What am I looking for on guage?

 
Will do tomorrow night. What am I looking for on guage?
You're looking for highest vacuum reading as you turn the idle mixture screws in or out. With a mild or stock cam, the reading should be relatively steady somewhere between 12-20 in/hg. If the gauge is bouncing all over the place, you will have to address what's causing it to do that before you set the idle mixture (vacuum leak, misfire, incorrect timing, etc.). Make sure you turn both mixture screws in or out equal amounts.

 
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