Why did Exhaust Manifold Fail?

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jungspike
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Why did Exhaust Manifold Fail?

Post by jungspike »

Our Manzo manifold failed today after less than 1,000 miles. The pipe for the waste gate broke off (see pics). Our set up: the waste gate had a short down dump pipe and was exhausting to the ground near the firewall. For about half of the 1,000 miles this down pipe had no support, so I am guessing that the unsupported weight of the waste gate and pipe vibrated and caused the failure?

I am attempting to get a refund, but I have some questions:

1) Has this happened to anyone else? I did a quick search and couldn't find anything.
2) What manufactures do people recommend for a quality product.
3) Do people using a dump pipe like ours provide any significant support to avoid failures?

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[URL=http://s1349.photobucket.com/user/ ... .jpg[/img][/url]
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hotbox240
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Re: Why did Exhaust Manifold Fail?

Post by hotbox240 »

I had a Phat KA-T manifold crack on me years ago in a similar fashion. Having the wastegate recirculated back into the down pipe definitely gives it more support.
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airman
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Re: Why did Exhaust Manifold Fail?

Post by airman »

A lot of folks weld extra bracing and make use of flex sections to eliminate any excess stress on the manifold and avoid an event like this. A lower cost item will use thinner-walled pipe and may not be as thought-through when it comes to stress concentration and preparing for repetitive heating/cooling cycles - increasing the risk of cracks. Sorry to see this happen to you!
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supakat
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Re: Why did Exhaust Manifold Fail?

Post by supakat »

I have had this issue happen to me twice with cheap eBay manifolds. I welded them back up and braced. They never failed again.
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i_slide
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Re: Why did Exhaust Manifold Fail?

Post by i_slide »

Same exact thing happened to me also with my Ebay style manifold withing the first 1000 miles. I also re welded mine, braced it and it never cracked at that position again.
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