header made from carbon steel???

[F8LDOSE]

I was wondering if anybody knows if schedule 40 grade, carbon steel steam pipe will hold up as a header for our trucks. It has a wall thickness of . 145". Also has a recommended working pressure of 723psi @ 800 degrees. A while ago somebody made one from schedule 80, but that has a smaller ID. Any opinions would be helpful. Thanks Jason

 

[F8LDOSE]

anybody????

 

[drees1]

It would work ok, except that it will rust from the outside, and thin out quicker on the inside than the ductile Ni-resist stock manifold. At high EGT, the steel will thin out internally. The Ni-resist used in the stock manifold is high nickel and will run at higher sustained temps before it evaporates internally. The internal thinning is the main cause of manifold "wear" in heavy trucks. Why not use stainless steel? You could make it a lot lighter, it will last, and look good. Since this type of project is all labor, the extra material cost is not going to make stainless a large percentage greater in cost over steel.

 

[Joseph Donnelly]

The tubing will have to be fairly heavy for strength since you are handing a turbo off of it. What are you trying to gain (airflow?) over the ATS three piece manifold? Given that the turbo housing is the "choke point" I would like to read some data about whether a better flowing manifold matters.

 

[tgbol]

I used schedule 40 pipe and weld ells to make up turbo manifold for my 4 cylinder Comanche. I seemed to have more warpage problems with it. It kept wanting to twist. I would machine it flat and it would do it again. Now I am no expert on metalurgy so I can't explain what caused it.

 

[drees1]

Did you stress relieve it prior to machining? Once you stress relieve it there should be no more warpage. Second what Joe says about hanging the turbo out. Keep the turbo close to the engine to reduce the stress on the manifold studs.

 

[F8LDOSE]

turbo flows 930cfm, so i need something that flows decent. Instead of spending the money on an ATS manifold, i can make my own and save some $$$. Still just undecided on what to make it out of.

 

[ronco]

Originally posted by Joseph Donnelly

The tubing will have to be fairly heavy for strength since you are handing a turbo off of it. What are you trying to gain (airflow?) over the ATS three piece manifold? Given that the turbo housing is the "choke point" I would like to read some data about whether a better flowing manifold matters.

That Joe is on top of things boy! Thanks for keeping both eyes open Joe!