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Old 02-07-2021, 11:50 AM
markvecc markvecc is offline
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Default Am I missing something?

Finished putting the engine back in my 72 gto and bolted the intake down with Felpro gaskets. I noticed this uncovered crossover hole in the head after I bolted it all together (see pic). Is there a special gasket that is supposed to cover this hole? Won't the exhaust come blowing out? Is there a block off plate that goes there?
Thanks in advance for any help.
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Old 02-07-2021, 11:55 AM
tom s tom s is online now
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Yes,there is a gasket that can cover it.Tom

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Old 02-07-2021, 11:56 AM
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That stays open.as long as you used 72 gaskets, they go below opening. 72 and newer.

Those are 72 or newer heads and intake, right?

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Old 02-07-2021, 12:00 PM
markvecc markvecc is offline
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So why is that open? Won't the exhaust come blowing out, or is is just for heat?

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Old 02-07-2021, 12:02 PM
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That is a separate hole not connected to exhaust on 72-newer.



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Old 02-07-2021, 12:13 PM
markvecc markvecc is offline
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Thanks, I knew someone would have the answer.

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Old 02-07-2021, 12:28 PM
markvecc markvecc is offline
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And yes, those are the original 7K3 heads and original manifold.

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Old 02-07-2021, 12:33 PM
markvecc markvecc is offline
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And yes, those are the original 7K3 heads and original manifold.

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Old 02-07-2021, 12:55 PM
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If I remember right, that hole is a non functioning closed off hole. It does nothing. I worried about that when I put mine together too.

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Old 02-07-2021, 01:38 PM
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What I found to explain the blind hole was that the purpose of this hole is to relieve heat from the cylinder head’s exhaust crossover passage.

Mopar 318CI - "The hole in question is to keep heat from the ex-crossover away from the oil under the valve cover which would quickly carbon-up if the air gap were not there."

Ford also did this.

Photo is of a Mopar head/intake showing the blind hole/gap.
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