Replacing turbo exhaust manifold - options?

[Einspritz]

So all this begs the question as to the original manufacturer?

[Preyupy]

BMW was casting their own parts and I can believe they did these manifolds as well. As far as making a pattern and recasting these they are fairly straight forward and I would guess a good foundry could do it without too much hassle,  

 

I’m guessing current materials and casting techniques they might be even better than the originals. Figuring out who to have do it and how many to make to amertize the cost to pattern and set up would be the next step..

[dlacey]

I am in Asia... i can find a quality casting house...

[Preyupy]

Buy the cracked one and use it as a pattern. 

[Preyupy]

NOS

[dlacey]

I got a cracked one and i have taken it to a casting foundry here in Malaysia. They will identify the composition using spark spectrometry:

https://www.spectro.com/products/optical-emission-spectroscopy/spectromaxx-metal-analyzer

Then they will quote me for producing a small batch of manifolds cast with the same alloy and machined to match my sample. I wondered if it might make sense to strengthen the design, given the common cracking just above the T3 flange...

So, lets wait n see what they say...but maybe i will come back to you proposing a group buy or turbo kickstart to meet their MOQ 

[Einspritz]

Sounds like a winner!

[dlacey]

My foundry is quoting USD350/pc at low volume, bare machined casting  (milled/flat surfaces & threaded holes, no studs).

 

How many do you think we need??

Edited June 8, 2018 by dlacey

[Einspritz]

I will be in for two at that price.

 

Given the fact that your foundry can test the composition of the manifold metal and make a pattern, do you think they could reproduce the exhaust housing for the turbo itself ? Unless others have a replacement.

 

I have identified a foundry here in the U.S. that makes turbos but have not had the time to investigate whether they will make a part for me.

 

It is of twin scroll design.

 

I was told by my rebuilder that the crack in the partition "was no big deal" other than the fact that there will be "leakage" between the two scroll paths.

 

Thanks for all your work.

[m6smitten]

+1 on the scroll.

 

I would be in for a ex-manifold.

[allbim]

On 3/21/2018 at 2:34 PM, Einspritz said:

Help me to understand; I just went out and put a magnet to the Turbo manifold and a Tii manifold I have around. The Turbo has a slight magnetic affinity and the Tii a bit more, but neither really strong as if it were steel.

 

If it were stainless, it should not be magnetic at all, yes?

 

The current manifold I use has thousands of track miles on it with no cracks. I think a contributing factor is the tuning and the gas; too lean.

 

Some stainless steel alloys are magnetic, some are not. Some of the non-magnetic alloys can become magnetic when work-hardened.

[artbo]

I believe the later manifolds had a higher nickel content hence less magnetic. This also helped with resistance to heat cracking. 

[pato2002]

I'd be in for a manifold if you get it going.

[JackF]

There are all kinds of SS alloys. I'll use the gun industry as an example. Back in the 70's when they began building SS guns they were using to high a grade of stainless and it was tearing up their tooling. They reduced the chromium content in the alloy to the point that they now make SS guns that can rust. Google SS metallurgy and alloys and pretty soon your eyes will be rolling in different directions.

[Yale]

Put me down for a manifold and are you making scrolls too? If so yeah!

 

I started asking Bmw again about their turbo program, as always no real information to report.