Need help identifying this metal line coming out the back of my carburetor

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Truck82

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The title explains this post. What is this metal line coming out the back of my carburetor for? Is it needed or can it be capped off?
This is a mid 70s (I believe 1977) Rochester 2gc carb.
Thanks so much for the help in advance, everyone!
 

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DoubleDingo

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If you have power brakes, no it can't be capped
 

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This line was tied into the vac line that went to the cruise control when it was a diesel. No more cruise control, so can this be capped?
 

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Unless you have other items needing a large vacuum port, cap it. I say cap it, when I mean plug it with a brass fitting of the correct size
 

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Not needed if your brakes don't have a vacuum boost.
 

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Unless you have other items needing a large vacuum port, cap it. I say cap it, when I mean plug it with a brass fitting of the correct size
Thanks I’ll get a fitting and cap it off
 

Truck82

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Not needed if your brakes don't have a vacuum boost.
That’s what I needed to hear. Thank you :D
Just wanted to know, can any vacuum port be capped off? Assuming it isn’t needed on the vehicle.
 

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That’s what I needed to hear. Thank you :D
Just wanted to know, can any vacuum port be capped off? Assuming it isn’t needed on the vehicle.
99 percent of the time. If in doubt post,sometimes they are a vent,not a vacuum line.
 

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Also used for tranny vacuum in some instances.
 

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