Spent a few hours today cutting up a brand new set of Arizona Speed & Marine headers. By default, they come with a 2.5" flange. I wanted a 3" flange. I called the company and they said that don't make a 3" one. They don't have a jig set up for that size collector. I called the "other guys" and was told basically the same thing. TOG has a part listed on their site for a 6 liter HD truck that says "3 inch headpipe". I said that would be what I wanted. Then after questioning him some, I found out that its the same header and 2.5" collector. It comes with a tube that bolts on to the headers at 2.5" then expands out to 3" to meet up with the stock 3" exhaust tube. They also charge another $150 for ceramic and are only mid length.

So I went ahead and ordered the ASMs with the intent to make my own 3" flange on the collector.

This is the before pic of the header. Great product except for the restrictive collector. Not everyone needs a full 3"s, but look how short the collector is. It would be a better product if the collector made a smooth merge to the flange instead of being so short:

<img src="http://www.z71.net/arizona.jpg" alt=" - " />

I went to work this afternoon and got the collectors out to a full 3". This isn't a very good shot of the comparison, but you can see the old 2.5" flange I cut off and the new 3" flange for size comparison. These headers have great 1.75" primaries that will flow much better now.

<img src="http://www.z71.net/flange.jpg" alt=" - " />

Here are both sides after expanding the header collectors out to 3"s, they layed out with 3" cutouts:

<img src="http://www.z71.net/headers.jpg" alt=" - " />
<img src="http://www.z71.net/cutout.jpg" alt=" - " />

Here is a shot of the 3" collector over the old 2.5" collector:

<img src="http://www.z71.net/stack.jpg" alt=" - " />

<img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />

 

Hey BigTex,

Why didn't you put the three inch collector on your Hamm headers?

 

Where is the 3" collector? It looks like you put the cutout where it was, or is it hidden? Would this be worth doing on an N/A truck? <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />

 

I haven't welded the collector on the pipe yet. The cutouts are just pushed up against the header for the picture. The flange may not be welded on until the whole exhaust is mocked up. That way we know the proper angle we need. This may not be worth doing on a NA truck, but for any one planning extra cubes, foeced induction or nitrous where you want to get the exhaust out ASAP, I'd do it. If you are worried about back pressure, you can always choke it down at the Y or muffler.

The Hamms are staying on my truck (for now at least). I may give them the 3" treatment at some time though. I reslly wish I had some 2.75" pipe and cutouts for the hamms. I think that would be good for my truck. The ASMs are for a different project.

<small>[ February 09, 2003, 08:26 AM: Message edited by: BigTex ]</small>

 

Looks great Richard. If I ever go larger cubes, I may do the same thing.

Greg