I have the UR cat back which I have yet to install, but I've decided to get a high-flow cat and install it at the same time. I was just going to get the UR one but I have a question about it and also figured I'd see if anyone had any other suggestions.

For the UR one, do I need the o2 sensor extender if I'm going to run the GST TBE map, or will the tune take care of the CEL?

I was also looking at the ETS one. It has a bend to avoid fitment issues with the driveshaft, but I'm not sure if that would help (or hurt) at all on the RA since it is listed for the Evo X (and I don't know if the layout of everything is the same between the two).

Also, are there any downsides to cheaper ones like the TurboXS or Depo racing (other than no wideband sensor bung)?

Any other suggestions or advice?

Edit: It looks like the TurboXS and Depo racing ones might have a spot for a wideband sensor.

 

I run a DEPO, No problems, it has the extra bung for the wideband.

Any HFC is liable to need a spacer to keep away the check engine light.
Any EVO X HFC will work with our cars I believe.An Evo CBE wont work though(just reiterating for others). I know my DEPO was used on an EVO X prior.

 

+1 Any HFC for an X will fit a RA. Just installed the mil.spec on mine a couple weeks ago. Perfect fitment. I bought the Vibrant spacer and haven't had a CEL yet. From all the research I did when I was looking for mine, brand really doesn't make a big difference. Pretty much just build quality and cell count. Got a great deal from a member here for a used mil.spec, otherwise I was going to get the Depo.

 

I have a Mil.Spec HFC also which has worked out well for me.

 

What would be a good cell count be? I may eventually get a HFC, but want to stay emissions legal.

 

I'm not sure you can...I'm sure the count will be high though.

 

Most are 200 cell count. The Mil.Spec is 100 and there are a few others I think. From what I've read HFC will still pass emissions. I'll find out next year, we only get tested every other year.