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Æternum
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This is normal. Nearly all the P18 housing VFs have the characteristic wastegate crack. 99% of the time, the crack is only cosmetic and does not affect the performance of the turbo.
 

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Discussion Starter · #5 ·
Ok cool, I've been reading kinda mixed things about it. So I just wanted to post the pictures to make sure the crack isnt abnormally bad. Or what problems could come from it. I really appreciate the feedback tho
 

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Æternum
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Ok cool, I've been reading kinda mixed things about it. So I just wanted to post the pictures to make sure the crack isnt abnormally bad. Or what problems could come from it. I really appreciate the feedback tho
Problems:
1. Pressure leaking from the crack making boost control difficult -- more lag or difficulty hitting boost targets.
2. Wastegate does not fully seat creating the same challenges as above.

The crack has to be pretty bad for either to occur.
 

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Discussion Starter · #7 ·
So then run it? Or is the crack pretty bad? I'm taking it to a metal shop today. See if they can do anything
 

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Æternum
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So then run it? Or is the crack pretty bad? I'm taking it to a metal shop today. See if they can do anything
Taking it to a metal shop will not really change anything.

The crack is due to the design and the casting process -- this is a combination of heat checking and thermal shock. If it were "repaired" it would likely crack again unless you were to significantly redesign the geometry of the housing.

It's just really common and I'd not worry about it - I'm 98% certain it will not affect performance. The crack looks pretty typical of the VF (P18) crack.
 

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Yeah, I have no experience with these like Zach but it would just bother me. However, I'd also worry about "repairing" it since you can't weld cast iron. You'd have to braze it. And you'd have to heat the part up to as close as the braze process as you could get before brazing. And you'd have to use a braze material with very similar contraction/expansion properties as the cast iron. For me personally I'd be afraid to use it, but if I did I'd use-as-is and not try to braze it.
 

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Æternum
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Yeah, I have no experience with these like Zach but it would just bother me. However, I'd also worry about "repairing" it since you can't weld cast iron. You'd have to braze it. And you'd have to heat the part up to as close as the braze process as you could get before brazing. And you'd have to use a braze material with very similar contraction/expansion properties as the cast iron. For me personally I'd be afraid to use it, but if I did I'd use-as-is and not try to braze it.
Then good thing you don't have a VF-powered Subaru.

At least 75% have the wastegate crack. My STi probably has that very same crack.
 

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Master Baiter
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P18 VFs are like plumbers...
 

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Discussion Starter · #13 ·
Sooo. I took it to an old man that rebuild turbo, all he does. Says the crack it's nothing to worry about at all. But i started to pick his brain about wheat be thought about it in General. He said you never really know there could be "gunk" in the turbine or whatever.. you have to put it on and run it and you'll find out in the first five minutes I was thinking I don't really want to put it on there and then it blows up its a big job to do.. so I asked him what about if I rebuild it myself or took it apart and at least looked at it and saw what kind of condition it was in. he told me I would break it hahaha.
 

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Sooo. I took it to an old man that rebuild turbo, all he does. Says the crack it's nothing to worry about at all. But i started to pick his brain about wheat be thought about it in General. He said you never really know there could be "gunk" in the turbine or whatever.. you have to put it on and run it and you'll find out in the first five minutes I was thinking I don't really want to put it on there and then it blows up its a big job to do.. so I asked him what about if I rebuild it myself or took it apart and at least looked at it and saw what kind of condition it was in. he told me I would break it hahaha.
You should be fine. As long as the turbo is good and that crack is the only issue I wouldn't be concerned.

I've come across some places where people have attempted to braise a cracked housing only to have it crack to the side of the repair or melt the solder off. Neither is something I would want to deal with.

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