P0420 code options
 

Looking to fix the CEL p0420 code on my 2013 brz. I have diagnosed the issue and found that the cat is well on its way out.
I am looking at potential options. Would I be able to resolve this issue by switching to an after market UEL catted header and tune? the OEM cat would cost me roughly same amount but offer no performance gain over what I am currently running (stock everything).

Buy a used OEM header, or go with an aftermarket with a tune if you want a little bump in power.

I'm seeing the only available catted header are from JDL, I might buy that. Anyone know what tune is best with this header?

I remember somewhere reading there marginal gains with a 2nd gen header.

It's unclear how things compare without a tune, but with a tune there does seem to be a nice gain.

https://youtu.be/7C_W6PoabzE