Is the gain (if any) with a cat back exhaust worth the money? I will not ditch the stock cat! I know how restrictive the cat is so that's why I'm asking. I am not even suppose to have this car and my wife will kill me if I start down the modding path like I did on my STi. If the gains are minimal, I will pass on the exhaust & just get a reflash next spring. For some reason, the 9 "feels" quicker than my old 04 STi in stock form. It's been almost a year since I let her go so that might be the reason.

 

if you dont want to get rid of the stock cat, then it will only help a little. maybe 10 hp..
I would go for a high flow cat and tbe. just my 2 cents

 

from what i've seen here on the forums, the 9 with a Forge MBC, catback(w/stock cat), HKS RS intake, 100 oct and 24.5psi boost does quite well. al, from dynoflash, claims 375whp on just these mods. i should say, the dyno claimed the 375whp. pretty impressive if u ask me.

 

With my car, the CB locked up gains later on (cams, tune). The cat and CB should be replaced together - no point freeing up one section to be blocked up again.

Just get minimal mods (mbc, TB, custom tune) and your car will be more powerful than my 04 with much more $ invested.

Your wife wont wont care or notice if you play your cards right. Take her for a spin in it

 

If you change the exhaust, your wife will notice right away and you'll have explaining or lying to do.... I don't know about the IX, but my '05 MR the cat back was good for about 10 whp and a lot of noise . I've since removed that exhaust and put the stock back on and I'm happier. Your car is probably as powerful as many previous EVOs ('03~'04) with lots of mods and even the '05 with exhaust/flash or piggyback. If I were you I'd leave it stock or go with a piggyback or reflash of some sort. That will make more power and leave your car basically unmolested...

 

I plan on getting ecutek in the spring. I want to get a few miles on the car and hopefully by spring there will have been enough 9's "tuned" so it will be a cake walk for my tuner. From just reading what I have read, I don't think at cat back is worth the money for 10 hp. I was wanting an angled tip HKS or Greddy but it doesn't appear I will be getting one. Thanks for the replies guys.

 

For "some" reason? You mean you don't know why the IX feels quicker than your stock 04 sti? Maybe because it puts down 30-40 more whp??? You bought a IX and don't know that?

Anyway, if you're not going to touch the cat, then I don't think a cat-back is worth the money and noise for the minimal gains. I do think that with an MBC and EcuTek flash, you will be extremely happy, because you will have over 300whp/wtq, which is as much as if not more than I have now will all my mods, which includes a catless TBE. You would be quiet as a mouse in church yet bet faster than me with only $750 or so spent...

Whatever you do, don't spend $800-900 on those exhausts you mentioned, though. Just get a Megan cat-back for $350 or so if you decide to get one...

 

buy the ssautochrome exhaust i sounds great looks good full tbe 275 check it out its not bad