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Discussion Starter · #1 ·
Just like the title says, im torn between the 2 exhausts. Either one i get will be mated w/ the Cobb AP st2 map. Which exhaust will give the most power/best sound quality?
Thanks,
Alex
 

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I dont know anyone personally with the Cobb tbe, although Im sure its a fantastic part. But I know a few local folks with the TXS stealth tbe and I think its great. Good quality, great sound, and very subtle looking. I actually wish I would have got the TXS from the start.
 

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i heard the cobb tbe on a friend with an 06 running stage 2 and it sounded quiet . . . but when he hit wot you knew he was comming . . . great sound and it looks like a stock exhaust from outside ;) :busted:
 

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Indiatr0n in yo IWDPL
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I love my Cobb Turboback, as do many many others on this site. One of the "downsides" that people will often point out about the Cobb TBE is that it pinches to 2.5" where the catback and downpipe meet (so, it's 3" from the turbo to the catback, pinches to 2.5", and then spreads out to 3" again). This pinch will cause such a MINOR loss in power, it's not even worth worrying about until you go to a bigger (big) turbo. If it bothers you enough, you can have a 3" flange welded in where the pinch happens.

The 2.5" taper is kind of a moot point anyways, because if you go with the TXS stealthback, the entire rear section of the exhaust is 2.5" piping, not merely a pinch like the Cobb. The TXS RFL-Ti is bigger piping but is RFL (Really F*cking Loud).

If you choose to go catted, the Cobb uses a high quality, metal substrate, high efficiency cat. I have the catted version, and I experience no boost creep.

The fit is excellent; no worries of pinching the A/C drainline, scraping on odd bumps, etc. Cobb's engineering is very well done. People complain that TXS's "biggie" downpipe hangs low and scrapes sometimes...I can't attest to this though.

The Cobb muffler has a nice growl to it, but isn't overly obnoxious. This was important to me, as I do a lot of highway driving. It's deep and you can tell it's there, but there's no drone (people say it's about as loud as the Invidia G200, but the G200 drones...). People can definitely hear me coming though, and it barks when you get on the pedal.

The fit of the muffler was better than stock, in my opinion. It tucks up real nice under the bumper, whereas the stock CBE would hang lower. Also, it's a pretty "sleeper" tip...nicely finished with a mirror polish, but it's not big enough to get much cop attention. An RFL-Ti muffler will definitely get more glances.

Here's some pictures from my install: http://www.iwsti.com/forums/showpost.php?p=645329&postcount=349

Hope that helps :)
 

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Love my RFL-Ti...have had it for almost 2 years. It definitely is LOUD at highway speeds but I have applied some sound deadening, which makes it bearable. It makes women and children scramble for shelter with a tap on the throttle! One point though...if you do go with the RFL-Ti, do not got catless with a BOV set to open. It's fun to see it shoot 4-5 foot fireballs out the back, but the fiberglass insulation inside the muffler will turn to glassy particles from the heat and you will go insane with the new ticking in the rear due to the particles banging around inside the can. It took me several maddening weeks to finally figure out where the noise was coming from and I ended up having to dremel a small section of the muffler so I could empty out all the insulation and remove the particles. I put the undamaged stuff back in and used the original cut-out piece along with metal tape (strong and durable stuff) and haven't had a single problem since over a year later.

Still a great system and definitely worth some added power over the Cobb system.
 

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Indiatr0n in yo IWDPL
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scorcher2005 said:
its not all 4", it tapers to 3"
Still, that reenforces my point - on a stock turbo, the TXS DP won't get you much more power than the Cobb. In fact, I think the Cobb Turboback vs. the TXS 4" DP + Stealthback would make less power, since it goes from 4" to 3" to 2.5"...
 

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Discussion Starter · #11 ·
WolfPlayer said:
In terms of fitment and quality ... there is no comparison at all: Cobb wins hands down. Period. I've worked with both.

In terms of performance, that remains to be seen. TXS has a larger downpipe. But, if you go catted then Cobb is using a much more free-flowing cat.

t


Then why did you choose APS? And is it the 3 or 3.5"?
 

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scorcher2005 said:
Then why did you choose APS? And is it the 3 or 3.5"?

well, considering this is a comparison between the cobb and the txs he was only commenting on those two.
 

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scorcher2005 said:
Then why did you choose APS? And is it the 3 or 3.5"?
I chose APS because I wanted a swappable metallic substrate converter. The TXS' converter is ceramic. Cobb's converter is not swappable. Also, I originally ordered the TXS. It looked like my kids welded it together. There are also lots of reports of this exhaust hanging really low. Furthermore, with their 'quiet' system you have a 3" midpipe that SLAMS into a 2.5" flanged axleback. I have no problem with a 2.5" axleback. But, at least make it taper and not slap into a flange.

I wish Cobb made a system with a swappable converter. If so, that would have been my primary choice. Also, they could then make that swappable converter have 2 different flanged ends: one that bolts to the stock catback and one that has no taper and bolts to a 3" catback.

t
 

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Discussion Starter · #14 ·
i really dont like the idea of the 3>2.5" taper. Also, what is Cobb's warranty? Because TXS has a 5yr warr. How is the TXS in the sound quality/drone issue? How does APS fare in the fitment/sound quality and their warr?
 

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I'm running stock VF39 turbo, stock injectors, stock fuel pump, got the full TurboXS RFL-Ti/highflow cat with Injen CAI. Got her dyno'ed other day, got 321 wtq, 278 whp. She pulls like a [email protected]#$%^& now :D

Kudos for TurboXS for a swappable cat if i decide to take it off.......... echeck time, i'll just put her back on LOL

I cam from the Blitz Nur Spec R catback and she's a lot more more mellow now. IMO, it's not really that loud to me. Either that or i'm deaf from my Blitz and it don't sound as bad ROFL.
 

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Indiatr0n in yo IWDPL
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scorcher2005 said:
i really dont like the idea of the 3>2.5" taper. Also, what is Cobb's warranty? Because TXS has a 5yr warr. How is the TXS in the sound quality/drone issue? How does APS fare in the fitment/sound quality and their warr?
You don't like the idea of the 3" to 2.5" taper (more of a "pinch" since it tapers back out to 3")...yet you would consider the TXS 3" to 2.5" SLAM at the catback ok? If you're comparing the TXS RFL-Ti to the Cobb Turboback, then yes, the Cobb has a pinch, the TXS does not.

To compare Apples-to-Apples in terms of sound, you would have to compare the TXS stealthback to the Cobb...and in this case, the Cobb has 3" piping throughout except the 2.5" pinch (smooth taper) at the catback. The TXS has 2.5" piping all the way back from the DP. Cobb wins.

If you don't plan to go aftermarket turbo in the future, the Cobb flows just fine even with the pinch.
 

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WolfPlayer said:
I chose APS because I wanted a swappable metallic substrate converter. The TXS' converter is ceramic. Cobb's converter is not swappable. Also, I originally ordered the TXS. It looked like my kids welded it together. There are also lots of reports of this exhaust hanging really low. Furthermore, with their 'quiet' system you have a 3" midpipe that SLAMS into a 2.5" flanged axleback. I have no problem with a 2.5" axleback. But, at least make it taper and not slap into a flange.

I wish Cobb made a system with a swappable converter. If so, that would have been my primary choice. Also, they could then make that swappable converter have 2 different flanged ends: one that bolts to the stock catback and one that has no taper and bolts to a 3" catback.

t
I'd rather have a 2.5" axelback that I can switch to 3" in the TXS unit, then a 2.5" taper on the cobb downpipe that I can't swap out. The Cobb definitly is a quality piece tho, can't go wrong with either as the 2.5" is only a restriction if your flowing over 400whp. The only problem I see with the TXS, is that the pieces that bolt up are all of different lengths then stock. If you ever wanted to rotated it wouldn't bolt up to the rest of the catback exhaust properly. Noting some welding couldn't get done but annoying non the less.
 

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Cobb isn't restrictive at all... i am running the Cobb catted TBE on a 20G and meth... not flow restriction at all...

if you want top quality go Cobb, no question there.
 

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Discussion Starter · #19 · (Edited)
no, im not getting the stealthback like you keep mentioning w/ the 2.5" slam. It will most likely be the RFL-TI. HP Outlets on NASIOC has it for $860 shipped!!! Cant beat that!
 

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Since it necks down to 2.5" doesn't that flow-wise make it flow like a 2.5" since? Someone with the big brain on flow can post...I do recall a rather lengthy explanation but can't recall any of it other than the above.
 
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