time to replace the catalytic converter

[laser3kw]

Hi Guys
I have to do some exhaust repairs on my 2000 Saturn SC1 -( manuals trans). It's a great car, 40 mpg in the summer, 35mpg winter.
I have to replace the flex joint attached to the down pipe. Unfortunately, It's a welded system. The down pipe, flex joint and cat are all one welded system. So when I do this I figure I will put a new Cat on. Is there a good cat for mileage? Is a performance or hi flow cat worth the money?
thanks

[ConnClark]

First, Do you live in a place where they check emissions?

They do make high flow cats. They don't always work as well as the stock ones.

[laser3kw]

First, Do you live in a place where they check emissions?

No. I really don't want to do a cat delete either. If I delete the cat, the down stream O2 sensor will not operate correctly. I detest a perpetual check engine light.

They do make high flow cats. They don't always work as well as the stock ones.

any recommendations? Stock replacement of otherwise?

[Hersbird]

They sell just the flex piece that you can attach to your existing cat, or you can buy the whole setup with a new cat.
It's Walker 53325 I think for the flex piece and $59 at Rockauto.com Then you can use a universal cat for probably under $100 (I see universal Catco converters on Summit Racing for $70) (or $116 for the Walker Ultra cat at Rockauto)
They whole assembly is about $170 but only the California version shows in stock there (I think it's fine to use a Cal on a federal, just not the other way around if you lived in CA).
If all you need is the flex pipe I would just get it and not replace the converter unless it is actually bad.

[oil pan 4]

Use a spark plug non fowler to cover the rear oxygen sensor.
It will trick the rear sensor into reading the exhaust leaner than it really is.
No check engine light.