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Discussion Starter #1
Hey you guys, How is the proper way to adjust the mixture scews on the carburetur? How can I tell which screw controls the gasoline and Air?

PS: I have a 305 with 2 bbll Carburetur.


Thank You.
 

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vacume gauge

find a manifold vacume source and connect the vacume gauge to there, usually if i'm not mistaken ,, there should be 2 adjusting screws in the front facing the radiator,,, I'd adjust the mixture screws where you achieve the greatest amount of vacume. I'd do one side , then the other , then go over them until you feel you have a good balance between each side. I'd turn them just slightly open ( 1/4 turn ) past the best vacume reading and see how the vehicle responds

Honestly , if it was mine , i'd think about getting a 2 barrel adapter to put a Holley 2 barrel on chevy 2 barrel intake and finding a good used Holley 2 barrel. I put a 500 Holley 2 barrel on a 327 once and it made a pretty big difference over the stocker. I had a 350 Holley 2 barrel on a 305 once and that worked good too.

Do you see any modifications in the future ??
 

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To answer what I think was your original question, both screws adjust the air/gasoline mixture. And the idle speed is a seperate adjustment on the linkage. There is not one screw for air and a seperate one for gasoline.
 

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Discussion Starter #7
To answer what I think was your original question, both screws adjust the air/gasoline mixture. And the idle speed is a seperate adjustment on the linkage. There is not one screw for air and a seperate one for gasoline.
Thanks, that helped alot.
 

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you still have not stated the tupe of carb.. which has different base settings for A/F settings... Exemple is holley base setting is 1.5 turns off seat. Rochester vary.. but I seem to recall 4.5 turns off seat.. Stromburg, Holley/webber, carter all have different base settings.....

you can turn your butt off but if you dont start with the base settings... you have no reference point ... and are screwing in futility:D:rolleyes:
 

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Discussion Starter #9
you still have not stated the tupe of carb.. which has different base settings for A/F settings... Exemple is holley base setting is 1.5 turns off seat. Rochester vary.. but I seem to recall 4.5 turns off seat.. Stromburg, Holley/webber, carter all have different base settings.....

you can turn your butt off but if you dont start with the base settings... you have no reference point ... and are screwing in futility:D:rolleyes:
I'm not going to lie to you. I don't understand more than half of the things you said.
 

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I'm not going to lie to you. I don't understand more than half of the things you said.
Oh boy.... Ok, let's start with this.

Look at the carb and note what it says on it. Name, casting numbers, etc.... Then everyone will know what TYPE of carburetor you're attempting to adjust. Especially since they all adjust differently.:yes:

Pics are a BIG plus!!
 
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