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Old 12-12-2012, 04:37 PM
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Originally Posted by sscanrun View Post
I have to drill a hole on the single plane intake. That means I have to remove it?
Not necessarily. "Manifold" vacuum only means a full-time vacuum source that is there even at idle. "Ported" vacuum is NOT there at idle, and that's the main difference between the two (there are subtle differences besides that, but they do not apply here).

So you can use a carb port that has manifold vacuum just as easily as using a vacuum port that's in the intake manifold itself, if you follow me.

If you have a Holley, the metering block has a ported vacuum port- do not use that. You can use a port that's located on the baseplate, but still double check to see that it has full vacuum at idle.

An Edelbrock carb has a manifold vacuum port on the front, driver side.
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