Are you usinng an electric choke or mechanical with a choke stove? That's what the cross over is for. In fact, I believe if you are running an electric choke and no smog crap, the manifold comes with plates to block off the crossover.

 

The carb I have has a manual, cable choke. The manifold itself has no cross over chamber. It blocks off the port in the head when the intake is bolted on. It's a Performer 2101.

Phil

 

It will be fine b/c my 406 has an older 'early '80's type 2101 on it.

pdq67

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Did the early small blocks have a coolant passage in the rear of the manifold? I don't think i've ever seen a SB manifold with a rear coolant passage,only in the front where the T-stat is located.

 

Don't worry about it!

pdq67

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