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1.6 exhaust manifold cracks

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#1
Alberto

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I cracked 2 exhaust manifolds during the 2021 season.  

 

Is this a normal wear rate?  Or am I just lucky?

 

I have an additional 4 other spares that I have collected.  Only 1 of them is not cracked (yet).  All of the cracks are where the runners meet the collector.  The studs to the downpipe on all 4 are either broken or stripped.  Fun times...

 

Seems like they are still available new at ~$260.  I wonder how long a new one will last.  Getting tired of replacing these.  


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#2
Steve Scheifler

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The first question when this comes up is whether you are using the bracket & clamp holding the downpipe to the eng/trans bolts. With that, yes they will crack eventually, without it they will crack sooner.

The ones I bought new were not pretty and had lots of obvious grinding on the welds (this was before that was allowed and one of the reasons the rule was changed.) I didn’t use those but suspected that a bit of careful bracing welded between the pipes above the collector might stop or at least delay the problem. No guarantees, that sometimes backfires on other headers, but these always crack in the same unreachable spots so even shifting the failure point somewhere else would be an improvement.
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Instigator - Made a topic or post that inspired other Broken record - You are starting to sound like a broken record.

#3
Ron Alan

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I've got 6 more you can root thru AG :)


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Ron

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#4
Alberto

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Thanks Steve.  I googled the bracket you mentioned.  Definitely have not been running one.  Will try and rectify that.

 

Thanks Ron.  If they're not cracked, maybe I'll buy some. :)


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