Help! I'm new to playing with my bug eye as I have only had it for 6 mths and need educating.
I have a standard 51 plate WRX and I want to start with getting the breathing right, starting with exhaust and filter. My main question is, is my uppipe likely to have a cat in it or not? Getting slightly mixed answers from various people.
I am happy in my mind with everything down from the turbo(Sport Cat and then pipe)
Whilst I'm on can anybody recommend an exhaust with sport cat that is reasonably discreet on noise levels? I need the car for early morning work run and don't want to wake the world up.

I apologise if this has a thread already.

Thank you.
GRW

 

Your motor will have three cats (I have the same though have decatted entirely), 1 in the uppipe and two further from the downpipe.
Uppipe swap will not really make any difference to noise. Generally, if you get a resonated 2.5" system, it will be a little quieter. I have a full 3" non resonated system and it can wake the dead.

 

Changing the uppipe to a non catted one, standard new age STI or Classic one are as good as anything for medium powered cars, will make a huge difference to the way the turbo spools as you will have just removed a huge restriction from the point where you do not want any restriction.

 

Thank you for that. Nice to learn one thing if not more each day. I like the thought of slightly faster spool. Might try to get a few quid from the scrappy for the cat!!!

 

I got 70 quid for the 2nd and 3rd cats alone.certainly worth getting a scrap value on it.

 

My wrx was mapped to 298bhp with cat uppipe. Decided to decate it as they say it helps. So have the map tweaked by duncan and made 290bhp with graphs to show. Boths graphs showed the same and saw no benifit unless i change the td04