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390 head identification

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mackb67 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote mackb67 Quote  Post ReplyReply Direct Link To This Post Topic: 390 head identification
    Posted: Jan/23/2022 at 8:33pm
Is there a way to tell if the heads on my 1968 AMX are square port or dogleg port without removing the partially rusted out headers that are on it currently??
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tufcj View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote tufcj Quote  Post ReplyReply Direct Link To This Post Posted: Jan/23/2022 at 8:36pm
You could remove the valve cover and get the casting number.

Bob
tufcj
69 AMX
74 Javelin AMX
67 Rogue

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you'll eventually pay for it...
and not have it.
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Heavy 488 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Heavy 488 Quote  Post ReplyReply Direct Link To This Post Posted: Jan/23/2022 at 8:43pm
Probably square unless someone swapped.
I believe casting under the cover should be 858.
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AMXFSTBK390 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote AMXFSTBK390 Quote  Post ReplyReply Direct Link To This Post Posted: Jan/23/2022 at 9:01pm
The casting number on a 1968 AMC 390 head is 318 8558 rectangular exhaust ports. 
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Heavy 488 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Heavy 488 Quote  Post ReplyReply Direct Link To This Post Posted: Jan/23/2022 at 9:26pm
I knew it had 8's and 5's in thereLOL
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Post Options Post Options   Thanks (0) Thanks(0)   Quote White70JavelinSST Quote  Post ReplyReply Direct Link To This Post Posted: Jan/24/2022 at 9:15pm
I thought the difference between the two was readily visible with a mere look see at them.
Nothing needs to come apart.
The square ports don't have the dogleg that appears in the bottom lower right of the port as shown in this photo. The square ports won't have that bump out in the headers or cast iron manifolds. 
70 Javelin SST, second owner, purchased 1972
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Post Options Post Options   Thanks (0) Thanks(0)   Quote BassBoat Quote  Post ReplyReply Direct Link To This Post Posted: Jan/25/2022 at 3:24pm
I have put dog leg headers on square port heads, so easiest is to pull valve cover and look for that 318 8558 number...

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