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COBB Tuning Cat Back Exhaust Stainless Steel (Part Number: )
COBB Tuning Cat Back Exhaust Stainless Steel (Part Number: )
COBB Tuning Cat Back Exhaust Stainless Steel (Part Number: )
COBB Tuning Cat Back Exhaust Stainless Steel (Part Number: )
COBB Tuning Cat Back Exhaust Stainless Steel (Part Number: )
COBB Tuning Cat Back Exhaust Stainless Steel (Part Number: )
COBB Tuning Cat Back Exhaust Stainless Steel (Part Number: )
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COBB Tuning Cat Back Exhaust Stainless Steel (Part Number: )
COBB Tuning Cat Back Exhaust Stainless Steel (Part Number: )
COBB Tuning Cat Back Exhaust Stainless Steel (Part Number: )
COBB Tuning Cat Back Exhaust Stainless Steel (Part Number: )
COBB Tuning Cat Back Exhaust Stainless Steel
Subaru WRX/STI Sedan 2011-2014

Features & Product Details

The COBB 3" Stainless Steel Cat-Back Exhaust System has been designed to improve the performance, the looks, and the sound in your vehicle. This exhaust system has been designed with minimal bends that reduce turbulence under pressure which relieves back pressure for increased horsepower, increased torque, and improvements in throttle response and reduced turbo lag. 

This exhaust system has been fabricated from quality 304 stainless steel materials which should last the life of your vehicle and endure the elements. The piping has been TIG welded and exhaust gasses go through a combination of 3" and 2.5" piping before exiting quad 3.5" polished tips. Exhaust hangers are welded onto the stock OEM locations so no further modifications are required on the chassis or body for fitment. 

Hardware, as well as a gasket, are included to make this exhaust ready for installation. It is also compatible with the stock, or COBB Tuning downpipe.



Brand: COBB Tuning
Exhaust Orientation: Straight Exit
Installation Hardware Included: Yes
Piping Coating: No
Piping Flex Joint: Yes
Piping ID: 76mm
Piping Material: 304 Stainless Steel
Piping Taper: Yes
Silencer Included: No
Tip Material: Stainless Steel
Tip Qty: 4
Tip Shape: Round
Tip Size: 89mm
Mfgr. Warranty: 1 Year
Condition: New Product
Return Policy:

RallySport Guarantee - 30 Days

Items that are covered under the RallySport Guarantee offer a 30 day no questions asked return policy.

RallySport Guarantee items may be returned within 30 days of the original invoice date and must include all the original parts and contents for a refund.

The RallySport Guarantee does not apply to products that have been modified, damaged, misused or abused. All returns require an RMA (Return Merchandise Authorization) Number, and freight charges are strictly non-refundable. For more information regarding our freight refund policy, please refer to our return policy page found HERE.
RallySport Guarantee
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12 Reviews
4.8 out of 5 Stars
5 Stars
4 Stars
3 Stars
2 Stars
1 Stars
Customer Photos and Videos
COBB Tuning Cat Back Exhaust Stainless Steel ( Part Number: 515121)
COBB Tuning Cat Back Exhaust Stainless Steel ( Part Number: 515121)
COBB Tuning Cat Back Exhaust Stainless Steel ( Part Number: 515121)
COBB Tuning Cat Back Exhaust Stainless Steel ( Part Number: 515121)
Fantastic exhaust! 2 years ago
5out of 5stars

I received this exhaust roughly 3 months ago and have been absolutely loving it! I was hesitant like the other about dishing out the $ for the exhaust when there's some more competitive pricing in the market but IMO this is worth every penny. The build quality is flawless, material, construction, and welds are all top notch. Install was fairly painless, it took myself and a buddy about an hour to install and fortunately everything lined up perfectly and bolted right up with 0 issues. 2 things I will say is like others have mentioned I would definitely recommend getting an oem donut gasket because mine was caked on to the flange. One more thing I will mention is to make your life easier would be to spray a little WD-40 or PB blaster on the rubber flanges when installing the axle back portion of the exhaust. Now for the sound, IMO the cobb exhaust perfectly emulates the boxer rumble. If your looking for an exhaust that's going to wake up the neighbors or set up car alarms I would look elsewhere. The exhaust is fairly tame under 3000 rpm but once you rip it WOT it sounds amazing! There are some days I wish it was just a hair louder but for livability and drivability for your day to day commute its perfect, loud when you want it to be and quiet when you don't. There's also no drone that I've noticed at any speed, Just go and dish out the money, you won't regret it!
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1 of 1 people found the following review helpful
Spring bolts NOT included 3 years ago
4out of 5stars

After spending about three hours peeling the rusting mess of a stock exhaust off of my 2011 WRX and chiseling off the old donut gasket with a hammer and a screwdriver and drilling out the holes from the busted spring bolts (that took more than an hour for one of them), I finally got to put the exhaust together. It went together perfectly and easily since the Y pipe is a separate piece (makes it much easier to install). But then I noticed that there were 6 bolts and nuts, very high quality, but no spring bolts. Since my car was up in the air in my driveway on jack stands with a new exhaust dangling unsecured from rubber hangers, I couldn't just take everything off and drive to the store. I would have been pulled over for sure if a cop heard me. I was screwed. I had to call a friend to drive me to Pep Boys to get two new spring bolts. Luckily they had them. So be warned. This doesn't come with a donut gasket and it doesn't come with new spring bolts. Luckily I had purchased the donut gasket during checkout as it was a recommended accessory. After I had all of the parts in hand, the install only took maybe 10 minutes. It was seriously easy. I recommend using something like WD-40 on the rubber bushings. Without it, no bueno. With it, bueno! Initial impression of the sound after a solid afternoon of hard labor was that it was maybe 5-8% louder than stock at idle. Disappointed. But I said to myself that that's what is good about it because living with a loud idle day to day sucks. There's definitely more of a burbly sound than stock along with more vibration at cold idle. Then I drove it around for about an hour. Amazing sound! I love it! Very slight pops when revving the engine. Nothing like a Focus RS, but nice indeed. I have stock cats, no downpipe or uppipe. I have Cobb AP STage 1 and SF intake. Very very nice sounding exhaust with the intake. When you hit the gas, especially under a bridge or in a tunnel, you will be blown away! Sounds so cool. Then throw it into 5th for stealth mode. An additional plus: with the seats folded down, the box that the exhaust comes in fits perfectly into the trunk/backseat right up against the front seats. Beware, the box is a heavy bastard. Wear gloves because the straps will cut into your hands. If you have UPS Mobile and set your deliveries to always go to a UPS store, beware that this package is too big for them. So they will deliver and leave it at your door. Very nice packaging, safely packed in with lots of bubble wrap and additional spacer boxes. I kept the outlets covered during the install so they wouldn't get scratched. The final reveal of them blew me away. Just beautiful. I don't know why I waited so long to get this exhaust. Mirror finish. The welds have cool rainbow patterns in them. It's truly a thing of beauty. Perfect fit in the car. I didn't have to adjust a thing. I tightened the spring bolts keeping everything else bolted up but untightened. Then I tightened the Y-pipe to mid-pipe bolts. Then I tightened the passenger side bolts and lastly the drivers side bolts. Everything just lined up.
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2 of 2 people found the following review helpful
Quality Piece with perfect sound 3 years ago
5out of 5stars

If you are looking for an attention getter or something loud, this is not the exhaust for you. This exhaust gives a deeper rumble with absolutely zero drone at any speeds. Using cruise control, I can barely tell there is an exhaust, which is what I wanted. At WOT, it opens up but still not "loud". I'm running Tomei UEL and cat less down pipe too and very satisfied with overall sound and the welds on this thing are incredible. Is it a little pricey, sure, however you get what you pay for IMO. If COBB had this priced to compete with the Q300, this exhaust would be extremely popular and the sound is much more mature. Using just a jack, basic hand tools, and on the garage floor, took about an hour to install, fitment is near perfect with the driver side tips sticking out maybe 1/2 inch more than the passenger side but not noticeable unless you go out of your way to look at it. VERY happy with this quality COBB piece.
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1 of 1 people found the following review helpful
You'll be satisfied! 4 years ago
5out of 5stars

I like most were a little leary about shelling out the extra scratch for this cbe. We all know there are several more affordable, highly rated exhausts on the market. However, when it comes to a visual/audible upgrade its all about personal choice. Various YouTube reviews don't even do this cbe justice when compared to the drive test. It gives an amazingly consistent and deep tone when needed without being overbearing. The welds are amazing, the look of the stainless is amazing and overall it's absolutely worth the extra money for something that you'll be listening to for years to come. Install was a breeze as well. Highly recommend!!!
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1 of 1 people found the following review helpful
Very nice exhaust! 5 years ago
4out of 5stars

I just installed this exhaust on my 2013 WRX and it looks and sounds amazing! It was very easy to install and only took me an hour. However, when i went and drove my car for the first time i heard a metal chattering noise every time i let off the gas pedal. The chattering was coming from where the mid pipe was hitting the factory heat shield that's under the car. I was able to fix the problem by getting back under the car and bending the heat shield to give me some extra clearance. That took care of the chattering. Other than the fitment issue i had, this is a very nice exhaust. I feel like the exhaust is a little over priced but i would highly recommend it to anyone that's searching for a great looking and sounding exhaust.
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  • Q: Fitment  adameinstein13 years ago

    I have a 2012 2.0i Subaru Impreza and I was wondering if this exhaust would fit on my car given that got a new after market bumper to accommodate the exhaust tips. The list doesn't have my model but I'm hoping that's only due to the stock bumper.
  • Q: Can this be installed to a 2.0i premium Impreza?  adameinstein13 years ago

    I have a 2012 Impreza 2.0i premium and was wondering if this exhaust would be able to fit my car if I were to get a new aftermarket rear bumper to fit the tips. The list doesn't have my model on it but I'm hoping that's only because of the bumper...
  • Q: Gaskets  Matt_G4 years ago

    What replacment gaskets are need with this exhaust?
  • Q: COBB vs. SPT  WesternSTi4 years ago

    How does this COBB Catback compare with the SPT in terms of deepness of sound, sound decibals, etc?? Anyone go from the SPT to the COBB? At some point I want to get a new exhaust, but the SPT is good for now. Is this a great exhaust to upgrade to?
    • 0 of 0 people found the following answer helpful

      A:  This Cobb catback is generally considered to be 'one step' above SPT in terms of volume and tone. This is a nice upgrade from SPT and it will be louder and deeper.

      Zach G. @ RallySport Direct 4 years ago  
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