(approx) 2 Hours
Light to Moderate mechanical skill required.
- How to Install a Roush Extreme Performance Catback System on your 2005-2009 Mustang GT and GT500
The Roush Extreme Performance Cat-Back System is available for any 2005 to 2009 GT or Shelby GT500 owner, who's looking for a muffler delete style exhaust that has a unique hollow growl, deeper and more aggressive than stock. Since this is a straight pipe design, the cost is kept at an affordable level around the $600 mark, making it easier on your wallet. Installation doesn't require any cutting or modification, so except one out of three wrenches on our difficulty meter, which we'll talk more about later on. Taking a closer look at the sound you just heard from this kit, Roush has put together a super aggressive cat-back that absolutely fits the muscle that the GT500 puts out. Both the Shelby and the GT models get a noticeable change in tone, and that's what makes this kit so unique. It's got the deep growl, but the tone sets it apart from others thanks to the lack of mufflers. Also, contributing to this is the incorporated mid-resonator design here just after the mid-pipe. Together this sound is loud enough to catch all the attention leaving your local car show, while having virtually no drone inside the cabin, because sound is more effectively directed backwards to the system, and out to through the rear. With all that said, I'm giving this four out of five on our loudness meter. It's definitely loud, but I don't think it'll wake as many neighbors as say the Borla Atak or the Corsa Extreme. One of the things people tend to forget when checking out an exhaust system like this is it can actually help slightly improve fuel efficiency. This is simply due to the fact that the engine runs into less air resistance and do it's job, ultimately leading to an increase in horsepower and tork as well, thanks to the higher flow system compared to a conventional one. Roush has this system CNC machine from Mandrel Bends that increase air flow through the 2 and a half inch 409 stainless steel tubing. This material is great for durability, and it's a good choice for those located in wintery weather areas like us here on the east coast since it'll hold it's own against salty roads longer than the aluminized options. To top it off, you'll see the 2 big 4 inch 304 stainless steel polished tips with the Roush logo embedded into the metal. This is definitely a styling bonus for the rear in my personal opinion. This is currently the only full cat-back with a muffler delete design available for the GT and Shelby models on AM. Given the fact it's 409 stainless, and one of the better materials on the market, I would've expected a higher price tag. The lack of mufflers did help to keep the price just about the $600 mark, making this a super affordable way to get some serious volume and tone out of your motor. You want to be heard, but you don't want to wake up the block, or annoy your significant other with the drone, this is definitely a good way to go. The insulation as I mentioned earlier will not be requiring any drilling or cutting or any of that nonsense, so you can expect a direct bolt on job here with simple hand tool like a ratchet, a 15 millimeter socket, as well as some jack and jack stands, or a lift if you have access to one. Overall, this shouldn't take longer than an hour or so in the driveway or garage, so I'm giving it one out of three wrenches on our difficulty meter. You'll obviously want to start off by getting the car in the air and support on jack stands or a lift. Once you're underneath you can unclamp the factory mufflers from the over axel pipes using a 15 millimeter, and then pull them out of there hanger isolators, setting them aside. From here, you can unclamp the over axel pipes from the factory h pipe or after market mid-pipe, if you have one, then set those aside as well. Pick up your new over axels from Roush with the included resonators you see here, and clamp them to the mid-pipe. From here, you can do the same with the muffler delete axel back portion of the system, then hook them into the hanger isolators in the factory locations, and you're good to go. That pretty much wraps up my overview and install. So, if you're the owner of a 2005 to 2009 GT or the lucky owner of a Shelby GT500, you might want to check out the Roush Extreme Performance Cat-Back Exhaust System. You can find it right here at americanmuscle.com.
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Features, Description, Reviews, Q&A, Specs & Installation
Technical Note. Americanmuscle recommends adding the 2005+ Mustang 304 Stainless Steel Exhaust Hanger Kit from the drop down option above, to provide more strength, stability and a cleaner installed appearance. If you have a 2007 Mustang you may need the kit for correct installation.
Fitment: 2005 2006 2007 2008 2009 Details
CA Residents: WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov
February 04, 2020
Best sound and loudest
This was on my 07. I had this paired with an off-road x pipe and wow did it sound great but for $700 I could’ve just bought some slp loudmouths and gotten the exact same sound. Kind of a rip off just for a name brand. Same style resonator as the loudmouths 1 aswell.Helpful (0)
January 10, 2020
Roush on 07 GT500
I had a Borla S-Type on before and nothing compares to this! This exhaust is amazing! I love the noise it makes and how aggressive it is. It took about 1-2 hours to install, extremely easy with a lift.Helpful (0)
December 22, 2019
This exhaust has changed the whole sound of my car making it sound amazing! It sounds just as I think a mustang should sound!Helpful (0)
July 05, 2019
Exactly what I was looking for, my mustang sounds 100 betterHelpful (0)
June 27, 2019
Went from Pypes Violator Axle-Back to this Roush Cat-Back and the difference was huge. The tone and volume is perfect. Cold starts are pretty loud but overall great.Helpful (0)
June 22, 2019
Roush cat-back exhaust system
Really looks great and sounds really great and very loud!Helpful (0)
June 22, 2019
Sounds amazing.!! I get lots of attention now from people on the way it sounds.! Definitely makes it sound like a muscle car. Very happy with choice of catback. Install was easy nothing to difficult with the roush. Having the right tools and help made it easier. Got done in about 1 hour and halfHelpful (0)
June 11, 2019
I’ve had this exhaust installed for a little over a month now and it is fantastic. It’s a very deep growl with no noticeable drone. Noticeably louder than my stock GT exhaust. The only problem I had was the fit was not perfect and one tip sticks out slightly farther than the tip on the opposite side. It’s not very noticeable unless you’re staring at the exhaust while the car is parked.Helpful (1)
May 31, 2019
Changed the whole tone of my RPM band. Sounds great at idle, very aggressive grumble. I get asked all the time if I had a 5.0 swap. Honestly sounds better as it doesn't have the horrible raspy tone of a Coyote. Get this with a decent H-pipe, heads, and the Hot Rod cams, and you'll have the meanest sound out there.Helpful (0)
May 13, 2019
GT500 purrs like a kitten
Love the sound and it does not have the "echo chamber" effect that I had on the previous exhaust system. I have Roush shocks and exhaust on my Shelby and I am extremely happy with both.Helpful (0)
What's the loudest exhaust setup I can possibly do available on American muscle
Hey Kev, So the loudest exhaust system would consist of longtube headers, an off road x pipe, and a resonated cat back system. Kooks long tubes with kooks off road x pipe, and either a roush extreme, flowmaster outlaw, pypes pype-bomb, or borla atak catback systems to finish the package. Those will be the loudest set ups that we carry.
Would it fit my v6?
You could install this Roush Catback, or any other GT catback of your choice, when combined with the Cut and Clamp X-pipe which I've attached below for you. Essentially, you'd be converting to dual exhaust. The x-pipe will reuse your stock catalytic converters and then bolt up to whichever GT catback you decided upon. Hope this helps!
Will this system pass California Smog inspection?
This Roush Extreme Performance Cat-Back System will not alter emission outputs and therefore will not single-handedly cause a smog inspection failure.
Do I have to Change my mid pipe? I have been looking for a while on trying to make my '07 California Special louder. I have listened to a countless amount of sound clips trying to figure out what I like best. After hearing this system on the Internet I think I found what I have been looking for. I was wanting to know if I needed to change to a different mid pipe. I love the deep muscle car note with the h pipe over the race car growl with the x. I hope to keep the h for this system. Will I be able to?
You do not have to change your mid-pipe for this particular catback system (I have this exact one in my car). You will gain a louder sound, especially because this system has resonators (that don't drone!) and no mufflers. However, if you want louder, deeper sounds, replacing your mid-pipe is a strong suggestion. Either go with an H-pipe or Pro-Chamber (even a little deeper sounding than H). Even better, if your state allows it, go sans catalytic converters (ie. off-road). You get a louder sound, cut weight from the existing (read: heavy) exhaust system, and also increase MPG as the car can breath and flow exhaust better. The choice is, of course, yours but at the end of the day, you can keep your existing mid-pipe as is.
How much hp will this add to an 05-09 Gt
This will not be adding horsepower to an otherwise stock Mustang. When looking at exhaust, the only piece you should really focus on in regards to power are the headers. Everything else will offer little to nothing, but either way it's negligible gains. You should focus on sound with catbacks.
This is not compatible with V6 models.
Yes, this will indeed be compatible with Item 69110. They are both designed to fit with their stock counterparts, so it would be safe to say they will work together.
Assuming the correct midpipe is used, this system can be used with long tube headers.
This is a straight pipe design, so the resonator diameter is going to match close to the 2.5" tubing diameter of the pipes.
Please contact your local DMV for laws regarding state inspection.
Yes, this exhaust should pass without any issues.
The Roush Extreme Performance Cat-Back System can be used with the BBK Long Tube Headers and BBK X-Pipe. However, please be advised that minor modification may be required to pair together.
Yes, this setup would be a great fit and sound!
This should work, yes. However, please note the Roush Valance is designed for the square tips so there may be a noticeable gap when used with round exhaust tips.
(approx) 2 Hours
Light to Moderate mechanical skill required.
What's in the Box
|Piping Material:||Stainless Steel||Tip Material :||Polished 304 Stainless Steel|
|Piping Size:||2.5"||Tip Size:||4"|
|Muffler Type:||None / Resonator||Fitment:||2005-2009 GT & GT500 Mustangs|