The port is for the automatic choke.

My stove plate and heat tube are original to the 1956 Chevrolet 235 powerglide passenger car engine.

The stove plate clamps onto the manifold and secured wit one bolt. stove plate
The routing of my heat tube to a Rochester BC carburetor. heat tube

Tim

1951 3100 Chevrolet
1951 Chevrolet Suburban Carryall
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