Cast iron or cast Aluminum?

Tleg93 · Post by **Tleg93** » Thu Sep 08, 2005 9:50 pm

What metal is the exhaust housing on the VF8? I've been told both. Looking at it, it looks like iron but that seems silly to me. Does anyone know? I found a guy to possibly weld my VF8.

Matt Monson · Post by **Matt Monson** » Thu Sep 08, 2005 10:43 pm

Based on the weight of it, and the rust, I would say iron. The headers and up-pipe are iron, so why not the exhaust housing too?

vrg3 · Post by **vrg3** » Thu Sep 08, 2005 10:47 pm

I'm 99% sure it is cast iron. Why does that seem silly to you?

I think cast aluminum would have a harder time handling the high temperatures seen in the turbine, and would radiate a lot more heat away than iron.

In any case, the welder will be able to tell if you bring it to him.

scottzg · Post by **scottzg** » Thu Sep 08, 2005 10:49 pm

I've never seen an alum exh housing.

vrg3 · Post by **vrg3** » Thu Sep 08, 2005 10:53 pm

Aren't the uppipe and crosspipe stainless steel?

Tleg93 · Post by **Tleg93** » Thu Sep 08, 2005 11:27 pm

Hmm, I can't remember who else told me it was Aluminum. Anyway, whoever it was that mentioned that my initial thought was that it was iron when we both looked at it at Matt's. It looked like iron. I guess someone telling me it was Aluminum cast some doubt on it for me. The welder here said he thought it would be Aluminum. I guess it seemed silly to me because I don't usually associate cast iron with car parts but I see that it makes sense. Does that make it more difficult to weld?

vrg3 · Post by **vrg3** » Thu Sep 08, 2005 11:36 pm

Were you looking at Matt's stock turbo or his 16G? Cuz the 16G has a ceramic coating on its hot side, right?

There are a few pieces of cast iron on our cars. Brake discs, calipers, and exhaust manifolds come to mind. All parts that have to withstand a lot of heat.

Cast iron can be hard to weld, yes... But so can aluminum. I guess whether or not it would be more difficult would depend on the particular welder's experience and skill.

THAWA · Post by **THAWA** » Fri Sep 09, 2005 2:41 am

I thought the uppipe was cast iron.

vrg3 · Post by **vrg3** » Fri Sep 09, 2005 6:37 am

I thought it had a flex joint in it.

Tleg93 · Post by **Tleg93** » Fri Sep 09, 2005 12:04 pm

Doh, the flanges are different.

Matt Monson · Post by **Matt Monson** » Fri Sep 09, 2005 4:42 pm

vrg3 wrote:I thought it had a flex joint in it.

I don't think it does. But I have a few out and can check. And I said the headers were cast, which they are. But you are correct the cross pipe is stainless...

vrg3 · Post by **vrg3** » Fri Sep 09, 2005 7:51 pm

Scott - Which flanges are different?

Matt - Maybe I'm wrong. I don't actually know where I got the idea that the uppipe had a flex joint, now that I think about it.

legacy92ej22t · Post by **legacy92ej22t** » Fri Sep 09, 2005 9:14 pm

The CES up-pipe has a flex joint.

Tleg93 · Post by **Tleg93** » Sat Sep 10, 2005 1:45 pm

The upipe I have sitting around has an uppipe has a flex joint.

Looking at my uppipe, the turbo side flange is wrong, unless I'm overlooking something. It won't bolt on to the turbo.

vrg3 · Post by **vrg3** » Sat Sep 10, 2005 3:48 pm

In what way is it different? Or is it completely different? I don't recall it looking wrong at a casual glance.

Is the uppipe you have sitting around the stock WRX one pulled from Majen? Or is it another one? If there's any chance it's from an EA engine that might explain the flanges being different.

legacy92ej22t · Post by **legacy92ej22t** » Sat Sep 10, 2005 3:54 pm

The up-pipe will have extra studs on it that are for mounting the turbo support bracket. They don't all attach to the turbo.

vrg3 · Post by **vrg3** » Sat Sep 10, 2005 4:39 pm

Oh, right... duh...

Post by **Legacy777** » Sun Sep 11, 2005 7:25 pm

The exhaust housing is most definitely cast iron. Standard cast aluminum would have a more difficult time handling the heat, and/or would be quite a bit more expensive.

The up-pipe & cross-pipe are standard steel piping. They are not stainless.

Here's pics of the stock exhaust
http://www.main.experiencetherave.com:8 ... /ej22t/26/

Tleg93 · Post by **Tleg93** » Mon Sep 12, 2005 9:33 pm

I forgot about the support bracket.

Tleg93 · Post by **Tleg93** » Wed Sep 14, 2005 7:15 pm

Condo's welding in Lock Haven, PA said they could easily weld it. So any local guys that may need this kind of stuff, check them out.

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Cast iron or cast Aluminum?

Cast iron or cast Aluminum?