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Discussion Starter #1
Hi all,
I am replacing the entire exhaust system. Two questions:

1-) Can I reuse the turbo-to-cat nuts?
2-) What kind of nut and stud should I use on cat-to-exhaust connection? Can I use any type?

Stay safe.
Ali
 

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Yes, you can definitely reuse the nuts on the turbo connection.
I think any bolts will work on the cat--to-exhaust connection, except of course Nylock nuts, which will melt the nylon. The heat abuses anything you put on there.
 

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A little tip for ya'.
Make sure you coat all the threads with a high temp anti-seize before assembly. It'll make disassembly a bit easier when that day comes.
 

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I assumed you used a wire brush......that is scale and can be chipped off, takes a long time little by little,not sure if the gasket will compensate the differences, will look tmrw. at new gasket I have.
 

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Depends on what gasket you have/use.

If you use this one you stand a better chance of it sealing with a surface that has some left over scale.

99067



If you use this kind, it will need to be completely smooth.
99068
 

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Discussion Starter #8
I have the second type. Is it possible to use high temp (2000degree) coat to create an even surface?

I have used wire brush on drill tip and chisel it, of no avail.
 

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Unless some new super sealant developed by NASA came out recently that I'm unaware of, use of any type of 'sealant' generally does not work.

You might be able to use (2) of those metal types gaskets instead of just one, That 'formed' part of the gasket is what makes the seal. If you can get enough of that to compensate for the gaps caused by the uneven surface you could potentially get a good seal. I've done it a couple times with success. Not something I really like to admit to but truth be told, sometimes you just have to do what you have to do.
 

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You can use exhaust paste, it's available at any parts store. I've used it to seal the pipes on my car at the clamp areas.
 

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You can use exhaust paste, it's available at any parts store. I've used it to seal the pipes on my car at the clamp areas.
Have to admit, I've never used that stuff. Always wondered if it would work or not.
 

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it is basically a hi-temp ceramic powder mixed with "water glass"/ sodium silicate to make a paste, which solidifies to a hi-temp 2000F. Easy to work with and apply...especially works great in the old style male/female assemblies, Do not recommend pre-cat applications
 

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For that, I would use a very thin coat, about the thickness of the scale. Apply with your finger.
 

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Nice. As long as it's flat to within half the thickness of the gasket you're good to go.

This is my machining OCD talking here. Should be just fine.
 

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Discussion Starter #19
Am I supposed to adjust the exhaust once it is installed?
Like tightening the nuts and bolts after certain movement etc?
I vaguely remember tightening bolts after starting the engine briefly or something like that.
 

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I only bolt the downpipes to their trans mounts and then tighten the bolts to the manifolds, no issues on the several I have done. On my own cars, I have over 80K on one set and 50K+ on the other without re-torquing.
 
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