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Discussion Starter #1 (Edited)
I am rebulding my holley 4150 700 DP and am not sure where the secondary stop should be set at. I have searched and for the most part I gather that both primary and secondary plates should be set so the transfer slot looks square. Is this right for both 2 corner and 4 corner carbs? When I took it apart the secondary was closed amost tight and the primaries where open more with transfer slot past square.
 

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If the carb has transfer slots on all 4 corners,then it is best to equalize them.This will give you more abilty to tune the idle mixture especiall on a large engine with a large cam since this would typically require a relativly large amount of air during idle and o run it off the primaries onl would require that he throttle plates be too far up the transfer slots and you wont be able to get the mix lean enough because you cant slow down the fuel rate in the transfer slots using the mixture screws.the exception to this would be if you have a very mild smallblock with a PCV valve then it may be worth running on just the primary side since you should need very little thottle opening to idle the engine anyhow.Good luck.
 

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I always set the front to get the "square" with the transition/throttle blade
Then I count the turns(1/2 3/4 1 1 1/4?) on the SEC. screw to get the secondary from closed to the "square"-I then reset the Sec. to closed + 1/16 turn
Then I adjust the idle speed with the secondaries but do not go past the square setting-if more idle speed is needed I start with pcv's,drilled plates,
or other alternatives
 

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if more idle speed is needed I start with pcv's,drilled plates,
which is the same effect as opening the sec butterflys up...

Set mixture scews and idle screw to mid factory spec
Then adjust the sec to get a reasonable stble idle
finish byFine tuning the idle with the mixture and prim idle screw, keeping them within fact spec.
 

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Discussion Starter #5
I will start with both prim and secondary with the tranfser square and see how fast my idle is and start from there. I will post back but it is going to be a couple of days before I get it started.
 
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