Adjusting the idle fuel mix screws on a Holley Carb - Vintage Mustang Forums

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post #1 of 3 (permalink) Old 05-19-2017, 01:08 PM Thread Starter
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Adjusting the idle fuel mix screws on a Holley Carb

This is a nice little write up from 2013, but it is still valid and covers a lot of people here have said in the past.

How to Properly Set up the Idle on Holley Carburetors

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post #2 of 3 (permalink) Old 05-19-2017, 06:16 PM
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Good article, although I usually seem to need to be on the rich side of highest vacuum..

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460 D0VE-C Heads w/CJ size valves, Lunati voodoo 227/233 cam, Edelbrock performer rpm manifold, FPA headers, Holley 950 HP carb, C6 w/2500 stall converter, 3.25 trac lock
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post #3 of 3 (permalink) Old 05-20-2017, 01:03 AM
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YA thats a nice primer and reminder.

If I tune my 450CFM holley for max vacc,~20, idle is like 850+ or so seems high with a munual. I richened mine as well, for better and worse. Blades full closed i get a nice 5-600 when warm with about ~16.

Will OAT or humidity effect vacc #s?
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