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My buddy and I will be going on a junkyard scavenger hunting expedition within the next few weeks. One of the yards we'll be hitting has what we call Motor Mountain, it's been around forever and I don't think they've ever sent so much as a valve cover off to be melted. The problem is that they're stacked (piled) ten deep and it can be a lot of work to free one.

I'm thinking that the more desirable engines will have the more desirable heads on them, and the casting numbers on heads are easier to pick out than the numbers stamped on the block. That would give me a starting point anyway.

Ideally I'd like to find a 455, but if looking for "XXX" on the heads might lead me to a killer 400 I'd take that too.

So my question is, what are the top choices in stock Pontiac heads and what's the easiest way to ID them in this situation?
 

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Here's a link with Pontiac head info on it
Cylinder Heads
The drawing near the top of the page will show you what to look for. The head casting number is on the center exhaust port. In that drawing "5C" is the casting number. As far as whats desirable, it depends what you want. In general, the big valve, small chamber heads are most desirable for a 400. These have 2.11" intake, 1.77" exhaust valves, screw in studs, and 72-75cc combustion chambers. These casting #'s would be 12, 12, 16, 62 to name a few. If your looking for a 455 just check the chart and see what head castings to look out for. For a 455 I think 4X and 6X heads from a 400 are pretty popular.
 

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I have a 2 455 blocks, and a virgin 400 block cleaned and ready for machining that i may be willing to part with. Also have set of 6x-4 heads, and 7m-5's i believe, will be cleaning out the old shop next week, i hope and will get a list of the parts i have on the shelf for you when i come by.
 

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I doubt very seriously that you'll find any of these there, but just in case --- look for any Pontiac head where the two center exhaust ports are round instead of D-shaped. Depending on what engine they're on, they'll be 68 1/2 Ram Air II's, 69/70 Ram Air IV's, 71/72 455-HO's, or 73/74 455-SD's. On these heads the casting numbers are sometimes on the front exhaust port instead of on the middle. Look for 722, 614, 197, 7F6, 16/X, R/96/A - but any roundport head is super rare and valuable.

Bear
 

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Discussion Starter #5
Thanks for the replies guys, this is just the kind of info I was looking for. I used to know all this stuff but then I spent 20 years raising my kids and all the good info got replaced with stupid sh*t like knowing all the words to every Winnie The Pooh song ever made.
Hopefully it won't take 20 years to unlearn THAT :lol:
 
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