Holley Help
Thread Starter
Pro
Joined: Jan 2009
Posts: 522
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From: Kings Park NY
Holley Help
I recently built a 383 with my son and installed a Holley double pumper. The carb idles well in park, but when I put the car into drive it wants to stall. If I adjust the carb to not stall it idles too high. I really not that familiar with double pumpers.
The carb is a Holley avenger 770 CFM, I still need to adjust the mixture with a vacuum gauge, but the car runs great for a out of the box carb.
Any tips on where to start. Thanks
The carb is a Holley avenger 770 CFM, I still need to adjust the mixture with a vacuum gauge, but the car runs great for a out of the box carb.
Any tips on where to start. Thanks
Melting Slicks
Joined: Apr 2023
Posts: 2,715
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From: Poplar Bluff MO
I'm not familiar with that carburetor but on my Holley 600 street warrior the first thing I did was adjust the float levels. The next thing I did was adjust the idle mixture. The next thing I did was adjust the idle speed.
JT
JT
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Joined: May 2006
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Move your vacuum advance hose from the ported position on the primary metering block to the manifold vacuum port on the throttle body front.
Also you have to check float level. Adjust mixture screws in Drive, parking brake on, wheels chocked.
Also you have to check float level. Adjust mixture screws in Drive, parking brake on, wheels chocked.
Last edited by MelWff; Today at 09:19 PM.
Thread Starter
Pro
Joined: Jan 2009
Posts: 522
Likes: 88
From: Kings Park NY
I set the float levels will do the mixture screws later tonight
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Melting Slicks
Joined: Apr 2023
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From: Poplar Bluff MO
For me adding an aftermarket carburetor I would follow the manufacturers instructions for setting the float level.
JT
Melting Slicks
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From: Poplar Bluff MO
JT
Old Pro Solo Guy
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From: Marlton NJ
Questions:
How big is the cam? Specs?
What is your vacuum reading both at idle? and In gear?
For an automatic, in gear, with a moderately big cam, you are going to have to get both the ignition curve and the carb tuning "just right"
Some automatics do run better with ported vac advance. But most are better with manifold vac. It depends on my two questions.
Start with the above vacuum reading(s).
Then set up the ignition curve, and the vac can.
Then do the carb.
There is an old adage that is still true:
"Most perceived carb problems are really ignition problems"
How big is the cam? Specs?
What is your vacuum reading both at idle? and In gear?
For an automatic, in gear, with a moderately big cam, you are going to have to get both the ignition curve and the carb tuning "just right"
Some automatics do run better with ported vac advance. But most are better with manifold vac. It depends on my two questions.
Start with the above vacuum reading(s).
Then set up the ignition curve, and the vac can.
Then do the carb.
There is an old adage that is still true:
"Most perceived carb problems are really ignition problems"
Last edited by leigh1322; Yesterday at 11:20 AM.
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I looked at the emissions sticker and my factory manual and can't find anywhere where it states to adjust the float level with the car idling in gear. I can't even find any mention of floats in my factory service manual.
For me adding an aftermarket carburetor I would follow the manufacturers instructions for setting the float level.
JT
For me adding an aftermarket carburetor I would follow the manufacturers instructions for setting the float level.
JT