Evening Fellas, it's been a long time since I've posted; everything has been going pretty good w the truck; hope ya'll are doing well.
I was climbing around w a flashlight under my truck the other day doing my post oil change inspection. I discovered both up pipes are starting to leak. I've got about a billion other financial obligations this fall so I'm going to opt for replacing the gaskets and doing the required steps necessary to reseal them. What do I need "chevy gaskets", new bolts, fasterners, etc to complete the repair? I've read the GM gaskets seal good but didnt see a part number. If anyone knows of a decent thread or threads that go through the repair feel free to add a link. I apologize for a series of redundant questions, usually not my style but I'll admit I'm being a little lazy.. Thanks guys.

 

If i were you ill do stock doughnuts with the up pipes expanded to fit tight on the doughnuts, mine lasted 100k without leaks.

 

Thanks, I actually saw you mention expanding them, great idea and something I'll do for sure! Stock doughnuts you say and not the GM ones?

 

Have never done the GM ones before, but if mine lasted 100k+ means they are not that bad at all. And yes expanding the up pipes sure did help.

 

OK, I gotcha. Any other tips or tricks one should be aware of for the job? Is ecpanding the pipes pretty self explanitory? I'm assuming I can do the job with my trans (5spd) in place but its just more difficult....

 

You will want to weld any deep gouges or holes up where the pipes have moved back and fourth. That surface area will be your biggest issue. Some used to cut the end off and flip to a new area with new gaskets. That would last like OE I would say. If I had another set of flanges I'd build you a bargain basement set of bellowed pipes.

 

Ok, I understand what your sayin. Noted.
Question, do bellowed up pipes help on the install because
they have that little bit of flex? Also I'm seeing them advertized
All over the place for $100 to $800.. Are there some out there that are total
junk? If there was some massive bennifit from using bellowed ups then perhaps
I would go that route.

 

Bellowed pipes would be nice but for our rigs they are $$ if you save you can buy them from riffraff for like $500 on the other hand if you buy the late 99 super duty up pipes and modify them those would be a bargain, if you have a long block 7.3 laying around this can be achived easy.

 

Permatex Ultra copper On all sealing parts
I don't even use header gaskets on headers anymore after using that stuff

 

I have read less than stellar reports of the SD dormant units. Its just about keeping the exh in. Are belloed units permanent or not? I'd like to think do it once and be done. If the bellows crack then its not. I have seen some crack. Who knows. I'll always error on building a set and get away from the stock junk no matter what.

 

Agreed. There are definitely better bread boxes out there for sure.
I'd like to do this one time I guess. Welding in bellows seems like a decent idea.
Suppose its would be "better" than stock to weld in bellows but still use the doughnuts? Maybe I can find a set of decent takeouts to prep them and have them ready. Question, how do the bellowed up pipes seal on the collector w/out doughnuts? Looks to me that the collector still has a bevel cut in it, not much meat for something to sit flat on??

 

let the pipe protrude up into the collector about a 1/2" and just seal a flat flange with header gasket material. That way the exh is pointing up past the sealing surface. It actually works quite well.

 

How would one do that? The pipes are flared out at the collector end. They couldnt recess inside it?

 

If you use the chevy gaskets, DO NOT use felpro 8194, they don't hardly crush down and clamp the pipe. I tried them the first time I did the up pipes, and they leaked. I switched to victor reinz PN f17250, they're made of a graphite material that crushes down nicely for a good tight seal.

 

they are a slight interference fit depending on carbon build up.