What Else to Replace When Replacing Catalytic Converter?

[SSTJ]

I'm preparing to replace the catalytic converter on my pretty-much-stock 97 SE, with about 100k miles.

I see that I can buy "universal fit" replacements, which would replace only the cat itself, by welding it into place. But I also see "direct fit" replacements, which include the down-pipe from the manifold. And then of course there are full kits, which include the down-pipe, cat, muffler, and tail-pipe.

If it's time to replace the cat, is it also time to replace any of these other parts? Is it a good idea to replace any of these other components at the same time? I can attach pics if helpful.

 

[TheBoogieman]

Is your cat actually bad? I only replace mine when they rattle or get clogged. I bought a universal cat for one of my 98's. I just cut the old one off and used a band clamp to install the new one. The Magnaflow direct fit had the down-pipe, cat and band clamp included. Only replace what you need/want to.

 

[macleanflood]

I've had the Walker down pipe to CAT on backorder from Summit for 6 months.

Might be a less than what you need/want situation and more of a what can you get.

My downpipe looks like a deranged exhaust shop made it...booger welded in the cat...booger welded in a cherry bomb...I want to replace everything BUT the CAT.

-Mac

 

[SSTJ]

Is your cat actually bad? I only replace mine when they rattle or get clogged. I bought a universal cat for one of my 98's. I just cut the old one off and used a band clamp to install the new one. The Magnaflow direct fit had the down-pipe, cat and band clamp included. Only replace what you need/want to.

Thanks. So you replaced both the cat and the down-pipe, but it sounds like the only reason was ease of install, not that your cat going bad meant anything was also wrong with the pipe. Right?

 

[SSTJ]

I've had the Walker down pipe to CAT on backorder from Summit for 6 months.

Might be a less than what you need/want situation and more of a what can you get.

My downpipe looks like a deranged exhaust shop made it...booger welded in the cat...booger welded in a cherry bomb...I want to replace everything BUT the CAT.

-Mac

Good point; it may be a matter of what I can get. But in your case, there was no connection between one part of your exhaust system going bad and another part also needing to be replaced. Right?

 

[TheBoogieman]

Thanks. So you replaced both the cat and the down-pipe, but it sounds like the only reason was ease of install, not that your cat going bad meant anything was also wrong with the pipe. Right?

Only the cat was bad. I replaced the other only because it had some rust I didn't like.

 

[macleanflood]

Good point; it may be a matter of what I can get. But in your case, there was no connection between one part of your exhaust system going bad and another part also needing to be replaced. Right?

I wanted to replace the downpipe for several reasons...one...rear main was leaking and it needed replaced...which essentially meant removing the exhaust anyways and that would facilitate putting in a v band clamp just forward from the CAT for easier removal forth with. Two...headers were cracked and the exhaust flange was pitted and the gasket was toast and the downpipe was frequently rubbing the front driveshaft. Three...the cherry bomb exhaust was loud and drony and most importantly I don't have any spark arrestor documentation limiting participation in certain organized events.

Thinking at this point of replacing the CAT...Magnaflow makes a stainless down pipe and CAT (federal) for $489 on Amazon and I know I've researched stainless flowmaster CAT back systems for under $500. Way more money than I want to spend...and I don't get to weld...but it's a solution.

-Mac