Kooks Mid with the Green Cats

[Chooch]

I am going to have to replace the stock manifoldss and cats and figured, now was the time to do it. I currently have a Solo Mach Catback system and from what I was told, scene, the Kooks with Cats should bolt right in and bolt right up to the Solo system. Now, question I have is with CEL. It states the Green cats while they dont flow as much as the "race" cats nor produce the same power levels, I wanted to stay away from going the customr tune route if I don have to, or at least make small changes.

Just need opinions of anyone has done this change, and did a tune need to be done with the Green Cats and Kooks Mids

[Zodiac]

If you are doing headers get a tune.

[BuildItYourSelf]

A tune is worth it with headers for sure.
Even a intake and cat back is worth a tune.
Personally a tune is the best first mod.

[Chooch]

I finally got my Kooks Mids and Green Cats installed and after a few days, got the CEL. Pulled the codes and got the both banks are showing low efficiency readings. Do the post cat O2 sensors do any mixture adjustment or does the front ones do that and thus due to the high flow of the cats, cause the reading to be off.

I know tunes generally shut off the rear o2 sensors, more concerns with the mixture and from what I understand the front o2 sensors do that. I have a Rotofab coming this week and a tune is in order, just want to be sure the rear o2 issue is not a damaging issue

Thanks

[s/c'd cav]

cheap way , get some spark plug anti-foulers , and drill a bigger hole in the end so the o2 fits and put them on the after cat o2 sensors

correct way would be a tune , plug your power and mileage will like you for it

[Chooch]

So net is no real issues as far as fuel air ratio etc... Just more or less the car going whoa, more flow then what I am used to in the post cat stream. And yeah, once the rotofab is done, going to get a tune done this way everything will be complete from intake to exhaust