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258 or 4.0 head
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irish13jeff View Drop Down
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Points: 181 		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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Points: 181 		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.
Please don't tell my parents I'm a truck driver..... They think I'm a piano player in a whore house...

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irish13jeff View Drop Down
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Points: 181 		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
Please don't tell my parents I'm a truck driver..... They think I'm a piano player in a whore house...

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irish13jeff View Drop Down
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Points: 181 		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
Please don't tell my parents I'm a truck driver..... They think I'm a piano player in a whore house...

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DaemonForce View Drop Down
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Points: 1070 		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
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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Points: 181 		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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DaemonForce View Drop Down
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Points: 1070 		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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Points: 181 		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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