Installing my 408W


New Member
May 10, 2003
I have recently installed a 408 into my 68', and its backed up by a performance automatic c4. my problem is that the instructions call for a vacuum line to go from the tranny to somewhere. where does this line hookup to. also are there any other vacuum lines i should know about. thank you all for your help
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68stroker said:
what exactly is manifold vac. and where is it located and what does it look like

Intake manifold vacuum. It is picked up at various places, some big blocks have a hollow carb stud, and lots of stuff has a nipple in the back of the manifold.
Holley carbs usually have a tap in the base plate as well.


For instance in this photo the nipples pointed to on c8oz-9a474-b and on c7az-9a474-a are intake manifold vacuum.

For more specific help we will have to wait for the small block guys to come along.


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