Holley idle setting question
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Joined: Sep 2010
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From: Tulsa Oklahoma
Holley idle setting question
I installed a holley 4175 (80555c) on 71 smallblock with automatic trans. I turned the primary idle speed screw one and a quarter turns to get idle to 600 RPMs while in gear. I then turned the secondary idle speed screw the same amount and rpms shot up to 2500.
Do I need to do a 1/4 or 1/2 turn in each screw until i achieve proper idle?
This is my first carb install be easy on me.
Do I need to do a 1/4 or 1/2 turn in each screw until i achieve proper idle?
This is my first carb install be easy on me.
Safety Car
Joined: Aug 2001
Posts: 3,683
Likes: 202
From: Waterford Mi
I found that you do not have to turn the sec screw very much at all before it is idling to fast. The reason to adjust the sec idle is to make sure you do not over adjust the main idle screw and put it out of the idle circuit area.
Le Mans Master
Joined: Mar 2008
Posts: 5,948
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From: Oxford MA-----You just lost the game!!!!
What I like to do is adjust the front idle screw so that .020" of the transition slot is showing under the butterfly, and then leave it there. adjust the idle speed with the rear screw.
Scott
Scott
