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258 or 4.0 head

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irish13jeff View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote irish13jeff Quote  Post ReplyReply Direct Link To This Post Topic: 258 or 4.0 head
    Posted: Jan/01/2019 at 3:39pm
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irish13jeff View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote irish13jeff Quote  Post ReplyReply Direct Link To This Post Posted: Jan/01/2019 at 3:43pm
I’m replacing the head bolts which are two different lengths. When I found the ARP head bolt kit it the sizes needed  it says the set with two different size head bolts are for the 4.0 head.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote irish13jeff Quote  Post ReplyReply Direct Link To This Post Posted: Jan/01/2019 at 3:45pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote irish13jeff Quote  Post ReplyReply Direct Link To This Post Posted: Jan/01/2019 at 3:50pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote DaemonForce Quote  Post ReplyReply Direct Link To This Post Posted: Jan/01/2019 at 6:58pm
So this means there is a solid head bolt kit available for the 258 w/4.0 head? This is great. Any work requiring replumbing of the exhaust usually strikes me dead unless I'm working on such a project in the city but when the successor to the 258 can't be swapped, a partial upgrade by swapping the head is more desirable and this looks like the way to go. That part number should probably be listed in catalog notes or something. Embarrassed
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American 304 2v | FMX | AM20-3.31

1983 American Limited
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Post Options Post Options   Thanks (0) Thanks(0)   Quote irish13jeff Quote  Post ReplyReply Direct Link To This Post Posted: Jan/02/2019 at 2:04am
can anyone confirm that the head pictures are in fact of a 258 head? Thinking the head may be of the last year’s of the 258 production 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote DaemonForce Quote  Post ReplyReply Direct Link To This Post Posted: Jan/02/2019 at 5:58am
Oh the title was a question. Ermm It's a 258 head. You have freeze plugs facing the port side of the head and there is a sandwich combination of the center exhaust ports. Are the bores for the head bolts made to take 1/2" or 7/16" head bolts? It should be 7/16" across all years.
1971 Javelin SST
American 304 2v | FMX | AM20-3.31

1983 American Limited
Jeep 4(.7)L S-MPFI | 1982 NWC T-5M (4.03/.76) | Dana30IFS/35-2.72
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irish13jeff View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote irish13jeff Quote  Post ReplyReply Direct Link To This Post Posted: Jan/04/2019 at 1:59am
They are 7/16”,  when I was looking for new head bolts it was a little confusing. Summit shows  all the same length head bolts for the 258 head. The two different length size set was noted to be for a 4.0 head conversion . My head bolts are two different lengths so it was throwing me off . Not an expert by all means so figured I’d ask for some clarification 
Please don't tell my parents I'm a truck driver..... They think I'm a piano player in a whore house...

http://www.legionofjeepers.com
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