Vacuum advance hookup
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From: No matter where you go, there you are. No VA
Vacuum advance hookup
I'm going to be installing a distributor with vacuum advance (my current dist does not have vacuum advance). I know that I want to hook it up to manifold vacuum, but my question is as follows. I have a manifold vacuum source on my carb (Holley 700cfm double pumper) that currently goes to the automatic transmission and also the electric choke. Is it okay to make another "T" off from this line and connect it to my distributor? I just want to make sure that it's not too much load for that source, or find out if there is something else I should do. Thanks for the help! 
Melting Slicks
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From: pr, frederick md.
you should have more than one vac tube coming out of you carb. also you have a tapped hole in you manifold that you can use as a direct manifold vac source if you need to. its on the pass. side back runner of the manifold.
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From: No matter where you go, there you are. No VA
Originally Posted by redc3
you should have more than one vac tube coming out of you carb. also you have a tapped hole in you manifold that you can use as a direct manifold vac source if you need to. its on the pass. side back runner of the manifold.
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From: South of giving a damn
St. Jude Donor '11, '17
Yeah, you'd have to get a barbed connector that would screw into the intake hole. Should be standard size & easy to find at the parts store.
Race Director
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From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
Originally Posted by ThereIsNoSpoon
Is it okay to make another "T" off from this line and connect it to my distributor? :
you mention a vacuum line to the choke??? perhaps thats the line that sucks in the warm air from the crossover....that will not work....do you have power brakes you could tap in to that line....but the line to the trans should work fine ....and you may have a ported spot on the carb....just experiment and see which is better ported or manifold and remember a higher idle does not means its running better.
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From: No matter where you go, there you are. No VA
Originally Posted by bobs77vet
yes Ts are ok....however you may want to check the vacuum at the end of the line to make sure it is adequate......
you mention a vacuum line to the choke??? perhaps thats the line that sucks in the warm air from the crossover....that will not work....do you have power brakes you could tap in to that line....but the line to the trans should work fine ....and you may have a ported spot on the carb....just experiment and see which is better ported or manifold and remember a higher idle does not means its running better.
you mention a vacuum line to the choke??? perhaps thats the line that sucks in the warm air from the crossover....that will not work....do you have power brakes you could tap in to that line....but the line to the trans should work fine ....and you may have a ported spot on the carb....just experiment and see which is better ported or manifold and remember a higher idle does not means its running better.
Does anybody know a part number for a vacuum connector that will screw into the manifold directly? It sounds like I shouldn't make anymore T's off of my current lines.
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From: BAKERSFIELD CA
the vacuum line to the automatic choke goes through the manifold draws fresh air from the port on the rear of the carb highest on the back that is vented into the air cleaner.the vacuum source for the choke comes from inside the choke housing.hook the fresh air source to the choke puts vacuum on both sides of choke and there will not be any air flow.vacuum advance is best hooked to ported vacuum supply. hooking vacuum advance to manifold vacuum will give you a surge at idle from timing changing with engine vacuum,worse if you have a rad cam.vacuum advance is used to advance timing when you have high vacuum and retarding it with low vacuum (acceleration) 
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