Ok, so I was at work today, ******* with the exhaust manifolds on a '40 Ford Deluxe, and was thinking about how there's no good headers for the H23, and not many for H22's (without spending a shitload of cash).

Then I started thinking about how DC recently started selling their H22 header with the 2.5" collector that everyone's been modding.

Since I work with two experienced mechanics, one of whom spent many years fabricating, I asked them what they thought of the difficulty of making my own header. I know exhaust shops make all sorts of custom exhausts, but usually not exhaust manifolds, and I didnt know if it was a matter of complexity, or need for special piping, or what. Also since I work at a place that sells/restores classic cars they're mostly domestic guys, and there's no Import/tuning shops in my area, but pipes are pipes, right?

Basically the conclusion of the conversation was that if I could get a pattern for the flange (where the header bolts to the head), or even just that flange itself from a stock header, that pre-bent pipes could be welded on (I'd want slightly larger primaries and a 2.5" collector). Also the problem of equal length-primaries came up, I said if possible I'd basically follow the factory/DC style pattern, but with larger pipes.

So basically, I plan to get a spare factory header to get measurements to make sure it'll still fit in the car, then some pre-bent pipes, cut off the primaries at the flange, clean up/grind the flange, and have my guy weld the pipes on.

So what I need you guys and your infinite wisdom for is pointing out any problems you see with this plan, pointers, etc. etc. My instinct tells that since I never see people's threads posting up their custom-fabbed headers it's not that easy, but I don't see what would be so hard considering all I have to do myself is obtain the parts and the guy I work with will weld it for me (he has badass equipment and he's good, too)

 

Building the header wont be too difficult, but finding the right combination of diameter and length and stuff like that is the tricky part. If you keep your lengths the same and basically stick with a similiar design to stock then theres a pretty good chance you will make more power.

I built one a few years ago for my H22, and it turned out pretty good until i had some ground clearance probs

As for the flange I would take an exhaust gasket to a machine shop and have them scan it and laser cut it for you.

Airflow and stuff like that can get pretty tricky, but if youre willing to do the trial and error thing you could definately come up with something good. Having access to a dyno would be a big help too.

good luck