I've seen a diagram on how both are installed and I'm curious know if anyone has either installed and is there a big difference.

 

one of the first things i did on my '12 was the cat back jcw exhaust and i've been very happy with it.

 

A large diameter (2.5 or 3") turbo back will yield the most gains.

But this is 2016 and we've all accepted global warming so hopefully it includes a high flow catalytic converter.

A cat back will probably do more for sound than for performance. I doubt you'd see a 5 hp increase on a dyno.

 

Even running a high flow cat isnt good for the enviornment so whatever. But its a lot harder to install turbo back than just a catback. you will hear a lot more turbo spool and sound with a turbo back and get better power

 

A high flow cat will still pass a sniffer test and OBDII checks. It's considerably better than no cat.

You might say "so whatever", but humanity is at a point where we can't just wave off things like this anymore.

 

I was not aware they would pass the smog test. Here in CA basically it has to be stock to pass. I ran a catless DP on my Subaru and it made a lot of power and it was fast but it did smell and not good for enviornment

 

I actually don't know if a countryman would pass since the requirements for it to be happy may be different than other cars.

California wouldn't pass you if they saw it anyway though.

 

Interesting.... if i do a turbo-back, it must have a hi-flo catalytic. OR...upgrade the ecu, turbo, downpipe, intake & cat-back... ??

 

It depends on what you're looking for. To answer the question directly, they both will yield results. If you are looking for noise, go catback, if you're looking for more power, go DP. Stock systems are designed for emissions and longevity, not performance, so either will provide power.


Given that, it depends on your end goal. The stock turbos are beyond limited because they are tiny, and can only flow so much air. If you are looking for a substantial change in performance, you would do well to research the dominator or disco potato turbo swaps, and from there, look into actual tuning (not the Burger), full exhaust, better intercooler, better injectors and build a more well rounded system.