Weld exhaust to downpipe, or weld on flanges and bolt it together?

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foamypirate

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Exactly what the title states. What would you guys do?

The factory exhaust had a slip joint that was clamped (downpipe into the pipe that goes into the cat). I am re-using the exhaust from my 87', which had the slip joint. It was stuck together so tight I had to cut it off. Now I can't decide whether to weld flanges on it so I can bolt it together and take it apart easily, or if I should just weld the stupid thing together.

What do you guys think?
 

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If its stock exhaust that you are not planning on taking apart again i would just weld it together.
 

89Suburban

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I like to use those band clamps like on the big rigs. Next time slice the nozzle of the bigger pipe connection longways with a cut off wheel so you can break the joint apart and still be able to put it back together. Being as you have two butt ends to put together now without a slip fit, it's best to weld I guess. I like to keep things so I can take them apart for access or to adjust them. That's where these come in handy, but I wouldn't use them for a butt joint:

http://www.gmsquarebody.com/forum/showthread.php?t=442

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Old77

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If its stock exhaust that you are not planning on taking apart again i would just weld it together.

x2. This creates fewer areas for exhaust leaks to develop and therefore fewer opportunities for headaches in the future :)
 

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As long as you know how to cut and weld, just weld it up and be done if it's in decent condition and not like you'd be having to tear it apart anytime soon.
 

foamypirate

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I like to use those band clamps like on the big rigs. Next time slice the nozzle of the bigger pipe connection longways with a cut off wheel so you can break the joint apart and still be able to put it back together. Being as you have two butt ends to put together now without a slip fit, it's best to weld I guess. I like to keep things so I can take them apart for access or to adjust them. That's where these come in handy, but I wouldn't use them for a butt joint:

http://www.gmsquarebody.com/forum/showthread.php?t=442
I looked into this, and they make clamps for butt joint connections, but there is weld on the outside of the diameter already, so I can't really slip one on.

x2. This creates fewer areas for exhaust leaks to develop and therefore fewer opportunities for headaches in the future :)

If its stock exhaust that you are not planning on taking apart again i would just weld it together.



As long as you know how to cut and weld, just weld it up and be done if it's in decent condition and not like you'd be having to tear it apart anytime soon.

Sounds like welding is the way to go then! It's pretty much brand spankin' new. It was on my 87' for maybe 2.5k miles.
 

foamypirate

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Got this thing welded up last night! Sounds great, other than the pesky manifold/collector leak that this setup has always had, even when it was on my 87'...I've tried everything to fix it and nothing works! Arg!!! Fortunately, that's only under moderate to heavy load, so I can deal. =D

I'll tell you what, it was a PAIN to weld this up. First off, I don't have a welding cart, and my gas bottle is strapped to my very much non-portable work bench at the moment, so I had to change over to flux core. Then, while climbing under the truck, I apparently bumped the wire feed speed from 25 to 50 (oops!). Took me a while to figure out why it was welding like shiat. Then there was hardly any room under the truck to fit my head with the welding helmet on, so I had to hold it up and funky angles welding halfway blind. Oh, and the setting sun kept triggering my mask too, which proved to be annoying, haha. Anyway, eventually got it all welded up, and put the trans crossmember back in, and all is well. Except my shoulders, from wriggling under and and back out from under the truck... :upyours:
 

89Suburban

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Got this thing welded up last night! Sounds great, other than the pesky manifold/collector leak that this setup has always had, even when it was on my 87'...I've tried everything to fix it and nothing works! Arg!!! Fortunately, that's only under moderate to heavy load, so I can deal. =D

I'll tell you what, it was a PAIN to weld this up. First off, I don't have a welding cart, and my gas bottle is strapped to my very much non-portable work bench at the moment, so I had to change over to flux core. Then, while climbing under the truck, I apparently bumped the wire feed speed from 25 to 50 (oops!). Took me a while to figure out why it was welding like shiat. Then there was hardly any room under the truck to fit my head with the welding helmet on, so I had to hold it up and funky angles welding halfway blind. Oh, and the setting sun kept triggering my mask too, which proved to be annoying, haha. Anyway, eventually got it all welded up, and put the trans crossmember back in, and all is well. Except my shoulders, from wriggling under and and back out from under the truck... :upyours:



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HotRodPC

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Ohhh Fugg !!! 89S found a new toy.
 

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He has way too much ****** time on his hands today.

But he would rather you were in his arms!
Foamy, you can use Ultra copper RTV on the exhuast donuts/collectors, let them sit for about 2 hours, then fire it up and take it for a drive...should take care of the leak, especially if you know exactly where the leak is. Package says sensor safe, and it will be below the o2 sensor, so its ok.
 

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