Custom fab tube style header/manifold

by **chevycrew** » Sat Jan 26, 2013 9:57 pm

Im having some flanges cut out locally then I will bend up the tube to build a shorty header to replace the stock manifold.

I plan on using the stock down pipe for a direct fit application.

3/8" top and bottom flanges with 1 1/4" sched 40 pipe for the tubes. (I have a bunch of tube already)

Back story:

I had a bad exhaust leak and I was thinking it was a cracked manifold. When I pulled the stock one out it happened to be only a loose bolt/gasket leak issue. The replacement heavy duty manifold was here already off of ebay (twice the weight) and I started comparing the 2. While the external dimensions were the same, the wall thickness was much greater.

This got me thinking, I dont want to choke this motor any further and the new manifold would be doing exactly that.

So, shorty header time!

by **Conner299** » Sat Jan 26, 2013 10:36 pm

Schedule 40 is some stout stuff... What material? 304, 316, Carbon steel?

by **chevycrew** » Sat Jan 26, 2013 11:01 pm

I don't remember what the pipe is for material. The pipe is .140 wall, 1.38" inside diameter. Should flow pretty good.

by **Conner299** » Sat Jan 26, 2013 11:24 pm

The place I work for specializes in valve actuation and piping for industrial purposes, that's why I was curious about your materials. We carry all the stuff I mentioned. If this works out for you, it might be an avenue I may just have to take a stroll down.

by **Moots1288** » Sat Jan 26, 2013 11:46 pm

Conner299 wrote:The place I work for specializes in valve actuation and piping for industrial purposes, that's why I was curious about your materials. We carry all the stuff I mentioned. If this works out for you, it might be an avenue I may just have to take a stroll down.

That looks like a butterfly valve for a big gas main.

by **Conner299** » Sun Jan 27, 2013 12:12 am

48 inch butterfly. Forget who it was sold to or the application. I do have a five minute video of the opening of it, after we had automated it.

by **Moots1288** » Sun Jan 27, 2013 12:16 am

We use those for gas mains here so I'm assuming that's what it's for lol

by **Conner299** » Sun Jan 27, 2013 12:34 am

Did we just kinda hi-jack a thread?

by **chevycrew** » Sun Jan 27, 2013 4:12 am

Its ok, no one is interested in a direct fit header option anyway.... Lol

by **Moots1288** » Sun Jan 27, 2013 9:55 am

chevycrew wrote:Its ok, no one is interested in a direct fit header option anyway.... Lol

I disagree! Lol

by **Conner299** » Sun Jan 27, 2013 9:57 am

Moots1288 wrote:
chevycrew wrote:Its ok, no one is interested in a direct fit header option anyway.... Lol

I disagree! Lol

by **mikekey** » Mon Jan 28, 2013 12:14 am

http://gmtnation.com/f43/kooks-4-2l-i6-header-5341/

Thought someone else was working on this.

by **chevycrew** » Mon Jan 28, 2013 12:59 am

That has been posted here as well. Problem is, have you seen the price tag?

Im shooting for a direct fit header that does not require any exhaust modifications and keeping the price down.

by **fishsticks** » Mon Jan 28, 2013 1:19 am

Going to try this on your HF bender?

by **HARDTRAILZ** » Mon Jan 28, 2013 1:20 am

Cheaper price be.great

by **Opeth** » Mon Jan 28, 2013 1:23 am

chevycrew wrote:That has been posted here as well. Problem is, have you seen the price tag?

Im shooting for a direct fit header that does not require any exhaust modifications and keeping the price down.

Yea I laughed at the price tag as well. I use to work with a friend who builds custom turbo manifolds and custom exhausts for a living, if mine breaks ill have him build me one. I can understand that price for initial costs of R&D if it were a one off custom piece since I use to be in that business, but if they really wanted to sell more of those they need to make it more appealing and be round the $500-600 range. Many of those who get the "crack" aren't usually looking for a HP gain, but rather an upgrade for better longevity in a new design.

by **fishsticks** » Mon Jan 28, 2013 1:48 am

The last go around of I6 headers came from StainlessWorks. They were $1200, didn't include a cat and needed additional fab to mate to the factory exhaust location.

These are $915, come with a cat and bolt in. What more do you want? I6 headers will always be low production. They have to charge something to make up their costs.

by **chevycrew** » Mon Jan 28, 2013 8:18 am

I know I dont want to pay $900 for something that really doesnt gain much. (Im not running a cat, and my manifold is still good)

Ill be using the HF bender since I have getting smooth bends down. The stock manifold is off with a buddy having 3/8" top and bottom flanges cut out for me. I might end up making it longer as I have tons of available space, but this will make it more unique to my build.

Its looking like it will end with the front and rear sets of 3 cylinders merging into 2, then those 2 merging to 1. Im going to try to copy the jeep 4.0L headers that have a design more for low end torque.

by **chevycrew** » Mon Jan 28, 2013 8:08 pm

by **bartonmd** » Mon Jan 28, 2013 11:45 pm

Awesome!

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