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Discussion Starter #1
Took the exhaust manifolds off my 410 today and there was no gasket. There’s a thin piece of sheet metal that I would call more of a heat shield than a gasket, but that was it. Is this normal? Should I go back with a gasket even though it didn’t have them originally? Below is a pic of the heat shield.
738759
 

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The stamped sheet metal gasket has a rolled bead around each exhaust port that gets crushed when the bolts are tightened.
FelPro MS95000
You can get a gasket that is made like what you were probably expecting to see.
FelPro MS9812

You'll have to google those numbers as I don't know how to post a link to a photo.
 

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No gasket is normal. If you're manifold is badly warped when you check for straightness, you should have it machined flat again. If it's only slightly warped, installing a gasket will work.
 

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When I had my orig 390 rebuilt for my 67, the prof engine shop said as long as you machine flat both mating surfaces at the same time, NO gasket is needed. I used SCJ exhaust manifolds.
Been ~ 15 yrs no leaks..
 

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Discussion Starter #6
Thanks for the info guys. So the question is, should I re-use the ones that are on there or go with new ones like awhtx posted? And if one of the ones he posted, which one?

We’re trying to keep the car concours correct but, of course, I can’t have an exhaust leak either, that‘s no good haha
 

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Discussion Starter #7
UPDATE: I spoke with my dad and we decided on new gaskets. My only question is which one? What’s the difference between the two that awhtx posted?
 

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A couple of weeks ago I was chasing an exhaust leak on a 390. The left side gasket was the MS95000 and the leaking right side was the MS9812. I used a MS95000 on the right side. The 2 gaskets in the box were marked LEFT and RIGHT.
 

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Discussion Starter #9
So on Fel Pro’s site under “Additional Fit Criteria”, the 9812 says “gasket for use with old heat shield”.

The 95000 simply says “heat shield”. Does that help anyone? I’m so confused haha.
 

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When I did mine I believe the factory repair manual said no gasket. I put a very thin layer of exhaust sealant. I also read somewhere about adding a thick metal type gasket can stress or crack a manifold too as it does like to be flexed.
 

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Discussion Starter #12

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Discussion Starter #14
Unless you can use them to make something else, like a lampshade or.....
I’m feeling festive this time of year. On the Christmas tree they shall go!
 

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So on Fel Pro’s site under “Additional Fit Criteria”, the 9812 says “gasket for use with old heat shield”.

The 95000 simply says “heat shield”. Does that help anyone? I’m so confused haha.
The 95000 has a raised bead around each port. Once you tighten the bolts the bead is flattened. If you take the manifold off and reinstall it you need to put a 9812 on the side of the 95000 where the raised bead used to be. That's how I understand it.
 

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Discussion Starter #16
The 95000 has a raised bead around each port. Once you tighten the bolts the bead is flattened. If you take the manifold off and reinstall it you need to put a 9812 on the side of the 95000 where the raised bead used to be. That's how I understand it.
Only further confuses me, haha. I just don’t get what the difference is. It sounds like to me that the 9812 is meant to be used WITH the old shield while the 95000 is meant to be a replacement for the old shield. Or I could be wrong.
 

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If you were me, you'd bolt it all up with no gaskets. If it doesn't make noise you'll be a happy man like I am. If it is noisy, then do the gaskets. Not a hard job.
I did shmear anti-seize on the mating surfaces as well as the bolts. Been driving it since spring 2016. No leaks.
 

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if you have an iron block and iron heads, there is no reason to use any exhaust manifold gasket. And no sealer of any type either.

This applies to the 289 / 302 family of engines as well as the FE's.

I was taught 50+ years ago to not use any exhaust manifold gasket, and hundreds of engines later, I've never had any issues with exhaust leaks. One must check the heads for warping, or if you are unsure of the correct way to do that, or don't have proper tools to do so, have a competent machine shop do it.THe cost will be negligible. If the heads are not 100% flat, a machine shop can resurface them and typically very little material is removed. Although I suppose it could happen, I've never seen a block that was warped, only cylinder heads.

Once the heads without gasket are in place and torqued to the proper spec it will take only a few seconds to a few minutes of the engine running for microscopic carbon to seal them the heads to the block PERFECTLY. And they will stay that way forever.

With trued heads, and no gasket, you NEVER have to worry about an exhaust manifold gasket blowing out. When a person elects to use an exhaust manifold gasket, it's only a matter of time before it gets burned out, and blown.

think about it.

Z.
 

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Discussion Starter #19
I’m definitely using a gasket. Still trying to comprehend the differences in the two though.
 
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