machina

Looking forward to more sound when my Cats arrive.

For anyone that has changed out the Cats only at some point, how much louder are they ?

utkinpol

cats replacement gives you power as you increase air flow. mufflers do not restrict air flow so changing them changes nothing. sound wise 200 cell cats add up a bit but not to the level when your kidneys start hearing it - if you keep stock mufflers.

if you are after sound alone - get sport mufflers. do not do 'gundo hack' as it screws air flow path and makes exhaust worse.
I ended up (due to my wife`s constant complaints) with fabspeed x-pipe cats and stock mufflers and I really like it this way now. With fabspeed maxflo mufflers I was roaring almost like a Harley at full throttle. Not as loud as with straight pipes of course, but loud enough to give a light headache on a long 40 minute + drive.

With 200 cell cats you get more masculine throatier sound but way below any annoying level and not like 'cup car' of course. May be 20% louder is a correct estimate. But it sounds quite well.

KeninBlaine

I like the sound of 200 cel cats. As mentioned above, they give a deeper throatier sound, and are not obnoxiously loud. They come to life more at higher rpms, where it counts. I had them with PSE on my last car. I think they are a good way to improve sound as well as possibly a little performance.

Bruce R

I have Gundo'd my muffles and installed AWE cats. Zero, none, no drone in the cabin at all but when you get on it it sounds so frigging great!

First clip just Gundo's with standard cats.
Next clip Gundo's and AWE cats. (listen from minute 2:29 especially)

http://www.youtube.com/watch?v=Lb0pc-7VPu0

http://www.youtube.com/watch?v=b0F1jkS1t5E

Oh and I've retained the stock tips, so it's pretty stealth