81 Dualjet (M2ME) vacuum lines

[Scary Fast atx]

My 81 C10 305 w 2barrel has Been battling some weird hesitation on my truck

Recently rebuilt the carb, replaced the fuel pump and new coil and module

It will run perfect and then sometimes at higher speed it will hesitate like it's running out of gas in the bowl

Now I'm checking the vacuum lines

Here is my diagram

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But my diagram doesn't have the vacuum port letters like on my other vehicles

I'm thinking the problem is where I'm running my vacuum advance to, any one know how the factory lines were hooked up?

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Previously the truck had the advance running from the lowest passenger side port labeled (full vac)

Thanks

 

[Scary Fast atx]

Well I got some time today, and put my vacuum gauge on the ports

Port B is full manifold vacuum and port on the bottom passenger side is ported

Fingers crossed that does the trick

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