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      02-08-2025, 10:44 AM   #1
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Header to Exhaust clamp trouble

I have a standard exhaust system with primary cat delete (test pipes) and I have an issue with the clamp which clamps the passenger side test pipe to the bottom of the header. The part of the clamp on the header side isn’t attached itself to the header and it just falls off when the test pipe is removed as it just slips over the header. I have tried a new OEM mesh crush gasket as recommended by a few places but it’s come loose again and is blowing badly. The drivers side doesn’t have an issue but that side appears to be fixed on the header hence my question. Does the clamp on the header need to be attached to the header or is it mean to just slip over? If it does need to be attached can it just be spot welded at a few places or does it need to be more? The clamp in question is the one pictured. It is commonly referred to as a bell and spigot clamp. Many thanks
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      02-08-2025, 11:14 AM   #2
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This is normal. One side is welded and the other side moves freely.

It seems super odd but that's how they designed it.

I would recommend a new set of gaskets, new bolts, and ensure that you have torqued it to spec. It can be easy to not tighten it up all the way with the gasket compressing as you are tightening it if you are only doing it by feel.
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      02-08-2025, 11:27 AM   #3
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Quote:
Originally Posted by drwankel View Post
This is normal. One side is welded and the other side moves freely.

It seems super odd but that's how they designed it.

I would recommend a new set of gaskets, new bolts, and ensure that you have torqued it to spec. It can be easy to not tighten it up all the way with the gasket compressing as you are tightening it if you are only doing it by feel.
Ok yes I had read it’s meant to be that way as someone else on here had lost the clamp while messing around with the exhaust off.. I’ll try that then. Do you happen to know the torque spec of the bolts? Thanks
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      02-08-2025, 11:29 AM   #4
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When installing the new hardware I’d recommend loosening all connections from to back then tighten the front first, working towards the muffler. It’s possible there’s some tension down the line pulling the connection apart, or misaligned pipes.
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      02-08-2025, 11:34 AM   #5
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Quote:
Originally Posted by Ajolives View Post
When installing the new hardware I’d recommend loosening all connections from to back then tighten the front first, working towards the muffler. It’s possible there’s some tension down the line pulling the connection apart, or misaligned pipes.
The entire exhaust is getting new clamps from the headers back so I will take your advise and make sure there’s no stress
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      02-08-2025, 11:57 AM   #6
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https://www.m3post.com/forums/showthread.php?t=1330067

Per this thread it’s 20 ft lbs; I just tighten the shit out of them until it feels like the nuts can’t take anymore. Never had an issue, the only issues I’ve had was when I didn’t use OEM gaskets, never closed right and had issues with leaks and rattling.

Last edited by Ajolives; 02-08-2025 at 11:59 AM..
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      02-08-2025, 12:37 PM   #7
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Quote:
Originally Posted by Ajolives View Post
https://www.m3post.com/forums/showthread.php?t=1330067

Per this thread it’s 20 ft lbs; I just tighten the shit out of them until it feels like the nuts can’t take anymore. Never had an issue, the only issues I’ve had was when I didn’t use OEM gaskets, never closed right and had issues with leaks and rattling.
Do you remember if the gasket you used was a compressed dark grey colour or metal wire mesh gasket. Cheers
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      02-08-2025, 12:47 PM   #8
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Quote:
Originally Posted by Jakee View Post
Do you remember if the gasket you used was a compressed dark grey colour or metal wire mesh gasket. Cheers
Compressed grey ones, stay away from the mesh.
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