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View Poll Results: Which Header to you prefer
Headman Header 42 23.46%
Doug Thorley 94 52.51%
Edelbrock 28 15.64%
Another 15 8.38%
Voters: 179. You may not vote on this poll

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Old 12-11-2013, 05:46 PM
Carnuck's Avatar
Carnuck Carnuck is offline
Join Date: Feb 12, 2011
Location: Gold Bar, WA
Posts: 6,474
Banks, Gibson and others make headers to fit the AMC 6 now. Better to swap to the HO head though!
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Old 08-31-2020, 12:38 PM
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rang-a-stang rang-a-stang is offline
Join Date: Oct 31, 2016
Location: Camarillo, CA
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Wow! Someone voted on this thread and woke it from the dead!

Nowadays, we don't have many options. I have the Hedmans on my truck. If you run Remflex gaskets, they seal.

BUT the ports on the Hedman Headers are TERRIBLE and do not match the AMC factory ports at all. Here is my experience with them with lots of pictures:
and parallel thread here:

I would love a set of Thorleys or others but I don't think they are available anymore. We could buy a set of shortys, I guess.
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Old 09-03-2020, 03:33 PM
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SC/397 SC/397 is offline
Join Date: Feb 01, 2010
Location: Michigan
Posts: 909
[quote=HARDCORE pacer]
Originally Posted by 78indian
i see hookers making a set now but they have rectangle ports??? never knew a amc motor to have rectangle exhaust ports.

67-70 had rectangle ports and if you look closely at the hedmans the dogleg is small enough to fit inside the rectangle port. Kasler headers are the best ones out there for an amc I have ever had.

I have had

$150 Hedmans - about 5 hours of porting just to make the flange ports match and then 2 hours of welding and filing to build up the sealing flange that was ground off during the porting.

$700 hooker super comps 2003- ports looked like some drunken idiot with a drill press was making abstract art not 2 of the ports looked the same. and they did not fit the application they wer made for. When talking to customer support they asked if I was another customer who was pissed off with there junk. After that call I sent them back they sent me another pair that was just as bad so those went back and I got my money back. mexican made junk

$200 bought a set of used super comps they were excellent ports were perfect fit was nise and they sealed up good. Thats what you get for moving the production facility from the us to mexico

$100 used kaslers- perfect ports perfect fit thick flanges thick tubing. What can I say except that holley bought them out and shut down the line and replaced them with mexican super comps.

never owned a set of doug thorleys or edelbrocks

One thing to say about the people who slag the amc header style manifolds. If you look at the modern cast manifold they have the same style as the 30year old amc ones. When amc went to that style of manifold they were able to get roughly the same output at 8.25 to 1 as they did with the cigar style manifolds at 10 to 1. I had my 500hp engine dynoed with header style factory manifolds and the good super comps and surprisingly there was only a 3% increase in power with the supercomps. If you are running less than 400hp then the headers are a waste of money. Go find the header style manifold as most of you know only one side of your fsj is cigar style replace that with one off a car or from one of the earlier fsjs that had them on both sides. You will not have leak problems. Also I like to run a dual INLET and SINGLE outlet muffler thats what I found gives me the best performance and sound.

BTW I had a large wright up about this a couple years back with pics of the different manifolds. This seems to be a recurring theme as they all are as we rotate through membership.

Here is another one:

An interesting side note.. Last year I spoke with one of they guys who helped develop and tested the AMC Free Flow exhaust manifolds. They really did their homework. I just wish that I would have taken notes of what he told me.
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