Can anyone tell me what the port is that's circled on the intake manifold?



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That's the exhaust cross over passage. It's function is to help warm the carb base when the engine is cold so that the fuel vaporizes quicker. In some applications it also has a loop in it that helps operate the automatic choke.
If you're running headers then the port becomes inoperative because the headers delete the exhaust heat riser valve. This is the thermostatic valve in the exhaust manifold that directs the exhust flow through the passage.

 

Thanks for the quick reply.. So if i had an intake manifold that did NOT have that port on it then it wouldn't cause any problems?

 

Thanks for the quick reply.. So if i had an intake manifold that did NOT have that port on it then it wouldn't cause any problems?

 

No, as long as the heat riser valve is disabled (if you're still running exhaust manifolds). That's a valve that is between the driver's side exhaust manifold and the exhaust pipe. When the engine is cold, the valve is shut and directs the exhaust flow from the driver's side head through the exhaust crossover and dumps into the passenger side manifold.
In reality, most of these valves are already seized, usually in the open position.
If you're running headers, the valve has already been discarded..
A lot of high performance manifolds delete the cross over because one, most engines are running headers and two they want to keep as much heat as possible away from the carb for a denser intake charge.
This is an FE but the valve, with minor variations, is the same on most Ford engines.

 

Well I don't see anything on my exhaust manifolds. I'm in the process of putting on some gt40p's and noticed that I didn't have that port on my intake manifold. Thanks!!!

 

Yeah, shouldn't be a problem.

 

Wolffman
Experience comment.
On my build I have a manifold with the ports built in ( Ed Performer). I blocked off the ports with some stainless.
I went through the brain games of "should I keep it for drivability, or get rid of it for performance".
It actually doesn't make a bit of difference to the cold drivability of the truck if you have a good running choke. I live in SoCal but I have talked to guys that live in the frozen north and they have no problems either.
So as Mike said, "fear not", it seems to me that it's an old tech fix that may have worked at the time but not needed anymore (as long as you make sure the valve is disabled or frozen open).

 

I don't even have a valve on the truck so hopefully it's just a port that goes to nothing

 

Then no worries at all

 

Thanks guys!