Post cat O2 sensor question

well, I went into the exhuast guy that does all my work for me today. I knew it was there but forgot, the O2 sensor in the cat. I was hoping to get rid of the cat and put a resonator in where it is now. So…my question is:
can I take out the cat and put the O2 sensor into the exhuast anyway? or will that screw with my air/fuel levels to try and improve emissions? Is there any easy solution or do I need to get a high flow cat or something? I have the cat back, and the elbow, and he is going to make the downpipe. Should I add a flex pipe into the downpipe?

Please offer any advice or experience.
Thanks all!

I’m personnaly goin to put in a high flow cat when i do mine. I like clean air. I’m not positive what the one in the cat does, but i doubt it would hurt anything to put it in the test pipe. I think it just tells the computer when ure cat is up to temp. Maybe unhook it and drive around and see what it does.

you will be fine! What I do is drill a 3/8 hole in whatever I am throwing in there and then grab a hammer and smash the treaded nipple off the factory cat and weld it on whatever I use. Ive even cut off the flanges off the factory CAT and rounded out the middle to 3" with a grinder and welded a pipe between. Costs $6 for a test pipe plus you time to weld them and grind the flanges. Ive pretty much done this on most of our inventory cars we had in Last summer.

all I did was pulled my cat out, knocked the crap out of it and put it back in. I was afraid it was going to sound tinny but luckily it doesn’t.

Is it an O2 sensor or just an exhuast temp sensor?

When I screwed it outta my cat it didn’t look like a O2 sensor it did look more like an EGT probe than anything.

agree^^ but unsure really, exactly what it is.

On a JDM car it’s supposed to be exhaust temp.