Where does the vacuum modulator on a TH400 go????

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1989 R3500

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Christian
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1989
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R3500
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454
I was rooting around under this truck I just bought and found the vacuum modulator line is off. I thought they connect to a hard line and go somewhere to the intake manifold. But I can't find any lines going down from the engine. It's a 454, TBI.

Does anyone sell the hard line?

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Frankenchevy

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Full manifold vacuum, sometimes teed into the same port as the brake booster.
 

Blue Ox

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I'd almost bet money that when yoi get it reconnected your going to find your engine smoking on decel and a loss of transmission fluid.

The only rational reason I can think of for not having it connected is that the modulator is blown. Still would have made more sense to replace it than disconnect it though.
 

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