Header to Y pipe gasket

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dh1989

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I'm trying to install a Magneflow catalytic converter onto a new set of JBA headers. The cat, Y-pipe, and headers were all supposed to be stock replacement fit. I found that the JBA headers have a rounded flange where they meet the Y-pipe whereas the original manifolds had a flat flange. The new header to Y-pipe gaskets that came with the cat are the stock style and don't fit into the rounded flanges on the new headers. I took out the metal insert that came with the gasket, and I can get the gasket to slip into place, but as I tighten the flange bolts it slides to the side. I'm sure it will leak if I try to use this gasket on that flange.

Here are some pictures. The first is the old manifold with the new gasket. The second is the new Y-pipe, which is the same style as the old Y-pipe. The third is the new header. Does anyone have any suggestions to help me get this to bolt up and seal?

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Frank Enstein

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It doesn't take a gasket. A little sensor safe silicone if anything but it should seal metal to metal.

Are there instructions with the headers?
 

dh1989

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I was wondering if that was the case. I just double checked the instructions, and they pretty much only cover installing the headers to the block. There is a vague mention of connecting to the rest of the exhaust system.

I've used Yale Muffler Cement with success on other parts. Would this be appropriate to put a light coat on the flange? It says it is safe for catalytic and regular exhausts.
 

PlayingWithTBI

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I have the Summit Racing shorty headers with the JBA "Y' pipe, just bolted it up without any silicone or gorilla snot. No problems plus, it's easier to disassemble later. That ball socket joint works fine by itself. Here's my JBA "Y" pipe with a high flow Cat. One thing I did do was tack weld the Joints where the muffler clamps go to prevent them from loosening up. I did that after I blew the Cat off of the Y when I hit the skinny pedal hard :Big Laugh:
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Frank Enstein

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I was wondering if that was the case. I just double checked the instructions, and they pretty much only cover installing the headers to the block. There is a vague mention of connecting to the rest of the exhaust system.

I've used Yale Muffler Cement with success on other parts. Would this be appropriate to put a light coat on the flange? It says it is safe for catalytic and regular exhausts.
I would do a dry run. Paint the connection (Either side) with a bright colored paint and let dry. Assemble the pipes loosely so they can be wiggled up and down with a firm tug. Disassemble and inspect the contact area. if you have a ring of shiny you won't need any sealer. If you use sealer use it sparingly to make sure is doesn't get into the cat(s).
 

ShawnB

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just an fyi, depending on ride height, this Y does hang a little low...

i have this very piece, snug all bolts in the flange first before tightening. i am going back through mine as it has developed a small pass side leak, probably going to add a sealant at the flange or in process of awaiting a new hotrod builder exhaust system to show up. i will be reworking these flanges.
 
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