Holley Question about Secondaries
Thread Starter
Safety Car
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From: Mundelein Illinois
Holley Question about Secondaries
There is a small screw at the bottom of the carb by the sendondary control rod. Is this the screw you turn to open the secondaries a bit, per lars carb sheet?
If so, do you have to take the carb off to do this or can you get to it with a small screwdriver while on the car?
Thanks again
If so, do you have to take the carb off to do this or can you get to it with a small screwdriver while on the car?
Thanks again
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You initially have to access if from the bottom, so you have to remove carb the first time.
Best way is to remove it and reinstall in the the other way so the screw slot is on top and you can adjust it without removing carb next time.
JIM
Best way is to remove it and reinstall in the the other way so the screw slot is on top and you can adjust it without removing carb next time.
JIM
Thread Starter
Safety Car
Joined: Nov 2004
Posts: 4,359
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From: Mundelein Illinois
Thanks Jim
Wouldn't you think the manufacture would install the screw from the top, or is this there way of makeing sure you don't mess with it.
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From: At my Bar drinking and wrenching in Lafayette Colorado
Yes, that's the secondary idle speed adjustment screw that I refer to in my setup paper. The BG carbs have the screw accessible from the top - Holley has a conversion kit for doing the same thing. Without the conversion kit, you have to take the carb off to do the setup correctly - I frequently remove and install a carb 3 to 4 times when I do the setup testing on Holleys in order to balance the idle speeds just right...
Thread Starter
Safety Car
Joined: Nov 2004
Posts: 4,359
Likes: 57
From: Mundelein Illinois
Yes, that's the secondary idle speed adjustment screw that I refer to in my setup paper. The BG carbs have the screw accessible from the top - Holley has a conversion kit for doing the same thing. Without the conversion kit, you have to take the carb off to do the setup correctly - I frequently remove and install a carb 3 to 4 times when I do the setup testing on Holleys in order to balance the idle speeds just right...
Thank you sir. I am going to my jegs cat ot order. I take it this is it.
http://www.jegs.com/webapp/wcs/store...10002_71952_-1
Last edited by spedaleden; Feb 1, 2008 at 10:27 AM.
Tech Contributor
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From: At my Bar drinking and wrenching in Lafayette Colorado
That would be it. Note that it cannot be used if you have a choke on the carb, and I don't think it's compatible with vacuum secondary carbs.
Thread Starter
Safety Car
Joined: Nov 2004
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From: Mundelein Illinois
I have Vacuum Secondaries and a Automatic choke. I did see a auto choke in the instructions but no secondary vacuum. I tried what Jim suggested by rotating the screw and I know have both primary & secondary equal. I don't see this as being a problem.
Any word of advice
Tech Contributor
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From: At my Bar drinking and wrenching in Lafayette Colorado
Once you have set the primary and secondary idle speeds to obtain equal airflow through both ends of the carb with an acceptable idle speed, there is no need for further adjustment - what little adjustment needs to be done can be done with slight movement of the primary side idle speed screw. So if you have it set, there really isn't an issue with secondary idle speed screw access. Good job setting it up right - that's the way to do it.
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Thread Starter
Safety Car
Joined: Nov 2004
Posts: 4,359
Likes: 57
From: Mundelein Illinois
Once you have set the primary and secondary idle speeds to obtain equal airflow through both ends of the carb with an acceptable idle speed, there is no need for further adjustment - what little adjustment needs to be done can be done with slight movement of the primary side idle speed screw. So if you have it set, there really isn't an issue with secondary idle speed screw access. Good job setting it up right - that's the way to do it.