Im thinking of getting a header kit and making my own going with a 1 5/8 primary, into a 2 3/4 or 2 1/2 collector and runnin duals out from there.

Anyone have any patterns or can offer advice it'd be appreciated.

 

Its not going to be worth it, I promise you.

You are much better off paying $500 and getting a nice set of coated headers delivered to your door.

You used a word like "pattern" and you live in NC so I take it you either have racing or at least fabrication experience, however making headers really sucks. Its even worse with the engine in the car.
I've seen guys that do this for a living for race teams take 2 weeks to get one set out the door. That was on cars with tighter packaging, but its still not fun.

Nevertheless, if you are hellbent on doing it, here is how you go about doing it imo.

1. Use your maifold as a pattern. Make the flange thick so it wont warp.
Get a WHOLE BUNCH of cheap, cold rolled steel elbows and staight pipes at all kinds of lengths and angles. Obviously, get couplers too. Start putting them together, changing angles and such. Make sure you have plenty of clearance with everything as they will both grow and be very hot. Close to the block is idea, but more difficult to attain.

Make sure you still have clearance for everything. Make sure your oil filter can still come out, wont pout on the headers etc. Make sure all the sensors can come off, make sure you can still get to everything. Try to make sure that it will COME OUT and go IN (assuming you are mocking it up on the truck, you'll be assembling it in the engine bay. This wont be the case for the final set)

Dont worry much about equal length, try to get equal bends/radii in from pipe to pipe. Bends are SO MUCH more restrictive than an extra few inches (even an range of a foot isn't a big deal). However, if one has 12 90* bends and one has 1 30* bend, its going to be less than desirable.

Then once you are done, draw a single line down each primary. It doesn't matter where or what side or if it spins around the primary. This is just so you can play connect the dots later and line everything up as it was on the truck. Start numbering everything so you can put the puzzle back together. Right now, it is only being held on by friction and will move around when you try to take it out. You'll probably knock a some peices off when pulling it out anyway.

So your line should look like this:
\--------1-1---------2-2----\
This way you know to connect the two ends that have a "1" together. The line shows you at what angle they should be connected (lines line up).
(red is coupler, obviously)
Take it all out, put it back together off your truck and tach weld everything so it stays in place. Drop it back in, make sure EVERYTHING is cool (including making sure it will bolt on and the exhuast port and primary are lined up!)

Return unwanted/unused peices of tubing. Make list of what you used in the final header. Get appropraite metal with the bends you need. Weld up. Feel free to overlap at junctions a good amount. For some reason, I usually see the first peice of tube tach welded on the outside to the flange and then fully welded on the inside of the tube. Make sure you are using proper precautions to make sure the flange wont warp (or mill/machine holes in it afterwards, what Id suggest).

Then you have to worry about collectors that wont leak. That generally sucks. Thats your fab skills in action.

Then weld in O2 bungs (as close to to the primary as possible). You may even want to put bungs in each primary so you can tune each cylinder, at a later time, should you desire to.

Running stainless steel will let you use header wrap and really keep a lot of the heat in, much much more than ceramic coating. If you didn't go crazy with lengths, you can throw a cat on the end if you plan well. Idea is to keep the cat close and hot.

Lastly, you'll want to make me set.
Thats all I can think of right now. Let me know how it works out or if you have any other questions.