Which cat to save/remove?
 

Hey all, I have a 2020 BRZ and am looking to upgrade my headers. My plan to this point has been to go catted UEL header and dual resonated front pipe. I don't want to go completely catless, but I do want to squeeze a bit of performance and sound out of the exhaust. (Sticking with stock mufflers for now.) What's the difference between that and keeping the catted front pipe and going catless header?

FYI, in the past I had a 330xi with the Active Autowerke signature exhaust and I learned to hate the drone. I don't want to go back to that.

I've put in the TRD intake and will use OFT for tune. I may also go flex fuel later this year.

Thanks in advance for the insight!

~Mark

Can't FF tune 17+ with OFT. FYI

You can squeeze out a little extra power with catless header vs Catted.

I would get a catless header then a Catted/resonated front pipe. Or just keep stock front pipe and decide later if you want it changed.

As the man said above.

I did the same and finally upgraded the from pipe to a resonated catted one paired with a TRD quad exhaust.

I have an EL header though.

Couldn't be more happier.

Hey all, thanks for the replies! I think I'll change my plan and go with a catless header and keep the front pipe catted.

NoHaveMSG, looks like you're right. I was looking at the Delicious Tuning kit and saw that they supported OFT and figured I was in the clear. Looks like they only go up to model year 2017. I guess I'll have to move to ECUTek to go flex fuel.

I guess the money I save on the header and front pipe can fund the ECUTek.

Thanks again for the help!

~Mark

Going with a catless header will usually trip a P0420. I hear there are mods for the secondary O2 sensor.

Also, I hear there now may be limitations on what ECUTEK will let you do too.

FWIW: Check into this before going too far.

OMG: @NoHaveMSG was RIGHT about something??

Oh crap, that's right. I forgot about that the tuning restrictions. Would OFT stage 2 take care of the code? Dang, maybe it's easier to leave the exhaust alone and just go straight to flex fuel.


Argh.

That's your best bet

Hey now. Even a blind squirrel finds a nut every now and then :D

I would talk to a tuner first before you do anything to see if what you want to do will work with the changes to Ecutek. Even if it is something that you plan on doing down the road a quick email will probably clarify a few things that us answering, as people who likely don't know how to tune with Ecutek, can't answer with certainty. FF hijacks an emission table(either secondary O2 or EVAP) to reference FF values. Hoping there is no issue there. I haven't followed up on what's going on with that in a bit.

There are ways around the new restrictions. Just got tuned recently for flex fuel with Ecutek without issues. Check out the Software tuning section of the forums and you'll see some talk about it.