I put the stock cat back back on, and lost 2 psi with my OTS cobb stage 2 map. So chances are you will loose a good amount of top end. Especialy cause you're car is tunned for that specific exhaust. Mabe look at the maddad whisper, or cobb. For something quiter. Good luck!

 

I'm also interested to find out, might be switching from a 3" turboback and thinking about doing a 3"-->2.5" intermediate pipe and run a STi axle back to quiet things down.

I recommend a cut-out if you want more power.

P.S. where the 2.5" on the exhaust may also affect power, say the 2.5" is where you cat-back bolts versus where the axle back bolts in

 

It would be the axle back only in 2.5". I have heard many times its much more important to have the larger diameter closer to the turbo but how much you could actually lose even at the very end of the exhaust I have no idea.

Edit: I'd like another brand with a stock looking muffler but I'd have to buy the whole catback which sucks (the cobb is $675, vs $360 for the turboxs axleback, and I've even got somebody who wants to trade with me for free) and then I'd also have to buy a $140 adapter to make it work with the 4" downpipe

tyler_sti did you mean catback?

 

Personaly I'd go with a whole different setup if noise is you're isue. The 4 inch dp is whats killing you.IMO. Id just buy a used 3 inch TBE system, and call it a day. You wont lose much performance, if any. And quiet things down a bit with the right cat back.

 

I'm definitely thinking about it but I really hate the idea. I love my exhaust. I don't think noise is nearly as big an issue as simply the huge fart can though. I'd like to try this first if I could.

 

The stock axle back is the most restricting part of the cat back, from experience. You will defiantly lose performance, but other than that. It should sound right around where you want it to. And my stock axle back didnt mate up to my invidia mid pipe, for refference. Might for you'res though.

 

Fortunately the turboxs midpipe does.

I'm thinking about putting the stock on and then welding a cutoff in the racepipe.

Has anybody gutted a stock muffler? Is the restriction in there or just inherent with 2.5 inch piping.

 

I have the full turboxs tbe with the racepipe. I had the rfl-ti muffler for about 1 year until i went the standard turboxs 2.5" muffler to stay quieter. Im tuned with meth injection on the stock vf39 making arount 325-330 whp. I did not feel any difference through the powerband nor did i pull any timing. You're not going to be losing any power until you start hitting 400whp+ and even minimal at that. I have been very happy with it so far.

 

I have the complete TXS setup with race pipe and the 2.5 in muffler and the car is running great and sounds great.

 

I have a 3 in custom cbe (straight pipe without resonators/mufflers) with the added stealth look of my stock STi polished tip! Looks great like rally style & sounds HELLA loud-i absolutely LOVE it! Haven't had any popo problems so far & it looks unique cuz all you ever see is gigantic cannon mufflers on other STis (especially all canked/bent sideways), while mine is straight! I haven't tested it for power figures but it's def stronger than stock! I came from a 03 SRT-4 so my STi HAD to be ****ing really loud for me to like it (all performance cars should be cuz race cars aren't quiet man)! Plus you have to unleash that badass boxer rumble to do the car some justice! I would personally stay the same diameter in the exhaust so you know for sure there aren't any restrictions & get whatever you like man!:tup::tup:

 

Thats cool man...I bet it is loud with what you got..dam...cops are pretty strict on exhaust loudness around here, so I opted for the 2.5in from txs. I actually own the car that the op is talking about(he sold it to me). He got pulled for the loud *** 4in rfl muffler from txs, so he put stock back on. I couldn't stand the stock one, just so quiet. But the 2.5in is perfect, not to loud and not to quiet...just right...lol

Loving the rumble!!!!

 

Thanx-if a cop don't see a bigass shiny cannon on the back (i just have the stock STi tip for stealth) then he won't pull you over! Just try to be quiet by coasting or quick shifting (hardly no revs) when around them (like me)! Turbos don't like restriction so bigger is always better with these cars, but if you like only 2.5 in then more power to ya! Go on Youtube & see/hear all the different exhaust setups so you get an idea before spending money (i went with my setup cuz of the cheap price & loud sound)! The boxer rumble is one of the best unique features of the car & muffling it would be a sin! Enjoy!:tup:

 

Thanx-if a cop don't see a bigass shiny cannon on the back (i just have the stock STi tip for stealth) then he won't pull you over! Just try to be quiet by coasting or quick shifting (hardly no revs) when around them (like me)! Turbos don't like restriction so bigger is always better with these cars, but if you like only 2.5 in then more power to ya! Go on Youtube & see/hear all the different exhaust setups so you get an idea before spending money (i went with my setup cuz of the cheap price & loud sound)! The boxer rumble is one of the best unique features of the car & muffling it would be a sin! Enjoy!:tup:

Thats exactly what I did. I spent hours watching videos of sti's with the Txs TBE with the 4in and 2.5in muffler. I wanted the Txs Brand since I already had the Txs Tbe. I didn't want to mix things up. But since im only 17, I don't need to be getting tickets anytime soon or ever. So i got the 2.5in.

 

The Simple run down is that the 2.5 muffler will not hinder your performance until you are around 400whp. Although this muffler has a quieter tone vs. the 3 inch RFL-Ti. Anything that gets the Really Freaking Loud tag, is exactly that. So we are working to meet you guys midway.

If you are over 400whp and you want to go with something that doesn't have the aggressive look we can set you up with a custom full 3 inch RMA. Same look as the 2.5 RMA but 3 inch from flange to tip. This is a direct only item for now as it is built to order.

Jermaine@turboxs.com

 

The Simple run down is that the 2.5 muffler will not hinder your performance until you are around 400whp. Although this muffler has a quieter tone vs. the 3 inch RFL-Ti. Anything that gets the Really Freaking Loud tag, is exactly that. So we are working to meet you guys midway.

If you are over 400whp and you want to go with something that doesn't have the aggressive look we can set you up with a custom full 3 inch RMA. Same look as the 2.5 RMA but 3 inch from flange to tip. This is a direct only item for now as it is built to order.

Jermaine@turboxs.com

Good info, Im only at 320hp so im good, and i like the standard look as well. Thats cool that yall are willing to build a 3in muffler with the standard look.

I probably would have gotton that if it was a mass produced item.:tup:
I guess thats the right way to put it.

 

you guys really need to start looking at dates before you bump 2 year old threads.