[65Dan65]

As the title says.
Just posting for conversation I suppose.
What's that center port for on the intake manifold? It was plugged on both sides with a hard dry crumbly substance. I used a shop vac right up to the hole while clearing it out. So hopefully I'm good there now.
Other random question would be, what actually happens under the intake manifold? Not the ports. But directly underneath where the rods can be seen going further down.
There seemed to be 'alot' of buildup on the bottom side of intake manifold, black, flakey I guess I would call both things carbon buildup but I have no idea if that's what it is.

Just trying to better my understanding as I go if possible

 

[awhtx]

The ports in the center of each head are connected to one of the exhaust ports in the head. They allow some hot exhaust to flow into a matching port in the intake manifold and heat the intake below the carb. This heat promotes better atomization of the fuel into the intake air improving driveability. Most aftermarket aluminum intakes do not have the matching port because heating the carb reduces performance. Some intake manifold gaskets do not have the hole punched out to block the flow of the exhaust gas. It's your choice to block the ports for performance or open them for driveability.

Oil in the lifter valley splashes up onto the bottom of the intake manifold. In high mileage engines it is not uncommon to find burned oil residue on the bottom of the manifold.

 

[65Dan65]

Thanks! Just even hearing the proper terminology is helpful. Got all the surfaces nice and clean. About to put it back together.