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I have 4 of this engines they all have same holes on heads above intake the engine I have running is blowing hot air out both sides is this supposed to be happening or what could be wring
 

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Blown intake gasket.
Pull the intake.Replace. Done
Not likely an intake mismatch, but maybe. Do you have history of this motor?
 

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To me it looks like older intake on newer heads. Because the non EGR and or divorced choke intakes are better looking junkyard grabs but everybody only has smog iron 400s that still run. Just my .02. You can see the open heat port in the shadow just south of the big chrome flake on the valve cover flange.

For this in the past, I have cut away the center part of each side of a gasket, made a plate from sheetmetal to cover the head hole and put orange RTV under it. The intake and bolts clamp it down. Stainless would be optimal but steel will run for a spell before it burns through. Blocking just one side is all thats needed if I remember right, passenger side. The exhaust note may change slightly after blocking the passage and she may be more prone to carb icing.

For what its worth, I've heard of breaking up an old piston, melting it in a skillet and pouring the passage full of that. Carefully. Thats more careful than I've got but I do have smog heads on my 455. :)
 

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It does look like what Idrivejunk suggests. That is why I asked about the history.It could be a mismatch
My GTO had the same open area as well. It does not leak. That is a common area for leaks though.
The intake I have on it now blocks the whole area .
the early heads and later heads have a slight difference in the height of the exhaust crossover passage , which is what you are looking at.
Look at this article:

 

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To me it looks like older intake on newer heads. Because the non EGR and or divorced choke intakes are better looking junkyard grabs but everybody only has smog iron 400s that still run. Just my .02. You can see the open heat port in the shadow just south of the big chrome flake on the valve cover flange.

For this in the past, I have cut away the center part of each side of a gasket, made a plate from sheetmetal to cover the head hole and put orange RTV under it. The intake and bolts clamp it down. Stainless would be optimal but steel will run for a spell before it burns through. Blocking just one side is all thats needed if I remember right, passenger side. The exhaust note may change slightly after blocking the passage and she may be more prone to carb icing.

For what its worth, I've heard of breaking up an old piston, melting it in a skillet and pouring the passage full of that. Carefully. Thats more careful than I've got but I do have smog heads on my 455. :)

Current engine with eldabrock intake hole not as big but still leaks View attachment 621229
Did I post in stealth mode or something? Block it off. I might have pics to explain if you don't understand but we can't help if ignored.
 

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This kinda array es at whose intake and which head’s, by that I mean casting number on head’s and part number or model name on the intake.

The rags in the pictures don’t help a lot they are blocking potential important views of these parts. A wider view would also be helpful to get an idea of the general layout.

Pontiacs can be rather difficult they made a lot of changes that are year and model specific so mixing parts can lead to some strange and unexpected problems.

Bogie
 
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