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Kooks High Flow Catted X-Pipe (11-14 Mustang GT w/ Long Tube Headers)

Item 65504
AmericanMuscle no longer carries the Kooks High Flow Catted X-Pipe (11-14 Mustang GT w/ Long Tube Headers). Please check out 1979-1993 Foxbody Mustang Mid-Pipes Exhaust for an updated selection.
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    Video Review & Installation

    Justin: If you've already picked up a set of Kooks long tube headers or plan on purchasing a seat in the near future, you are going to need to pair it up with a corresponding mid-pipe like the catted X-pipe that we have here. Now, the Kooks mid-pipe again will be for the owners who prefer that X-pipe configuration over in each pipe per se and would like to include cat for tough emission states. Materials for this particular product will be mandrel bent 304 great stainless throughout. And installation will require the use of a corresponding set of Kooks long-tube headers. Price point for the made in the U.S.A. mid-pipe will be right around 600 bucks and the install of the mid-pipe itself won't be all that bad. It's the long-tubes that will be the knuckle busting portion of the install. So, by itself, the mid-pipe we'll call it a strong one out of three wrenches on the difficulty meter with a detailed walkthrough to come later in the video. So, again, the big takeaway here, guys, that you need to be aware of is that you have to pair up this particular mid-pipe with a corresponding set of Kooks long-tube headers because trying to pair this up to your stock manifolds or even a different set of aftermarket headers will simply not work. Now, one reason in particular Kooks doesn't include a mid-pipe with their headers right out of the box is because they like to give 11 to 14 GT owners a lot of options when it comes to piecing together their system. And honestly, they're one of the best at it on the site. In fact, they have six different mid-pipe options currently for the S197 owners out there considering a Kooks long-tube header. And this includes three different X-pipes and three different H-pipes each with a catless or off-road version, a high flow cat like we have right here and then finally, their green cat as they call it, which will be an EPA-approved catalytic converter and your best bet in eliminating emissions-related issues. And again, I love the fact that Kooks gives you guys these kinds of options because honestly, again, they're the only ones doing it on the site. Now, that biggest option applies to the difference between the X and H-pipe. A lot of aftermarket header companies simply give you an X-pipe and that's pretty much it. And yes, the mid-pipe we are talking about here today does feature the X-pipe as you can see it right here and therefore, you can expect a little bit more rasp and a little bit more volume at the end of the day. But if you're the type of owner who craves that deeper tone overall, feel free to check out the different Kooks H-pipe options here on the site as well. But aside from the crossover styles, the rest of your Kooks mid-pipe options will be pretty consistent from a material standpoint. That does include the premium 304-grade stainless steel throughout, three-inch mandrel bent tubing but does step down to two and three quarter inch tubing here allowing this to work with your factory cat-back or a different aftermarket cat-back that features that factory style connection. It's also worth pointing out that these different mid-pipes from Kooks are also designed to work with a one in seven-inch and chatter from Kooks in addition to the slightly smaller one and three-quarter inch primary Kooks headers as well. Let's shift gears and talk about the installation, and since we are focusing in on the mid-pipe for this particular video, we'll call it a strong one out of three wrenches on the difficulty meter. To give you a better idea of what's involved for the mid-pipe job, here is the detailed walkthrough along with the tool breakdown. Man: All right. We're gonna remove our H-pipe now. Got a 15-millimeter socket, we need to loosen up these two clamps right here. Next, we're gonna reach up in between the transmission and the tunnel and unclip our O2 sensors. We're gonna push in our tab. Push really hard and pull. And we're gonna do the same thing on the other side. Next thing you wanna do is remove the four knots that hold the catalytic converters to the stock manifold. Now, we had a lot of trouble removing these bolts. We ended up just breaking all four bolts. You can get through them from the top of the engine compartment with a very long extension or an S-wrench that we used. Turns out it was easier to break the bolts instead of fighting them. So, that's what we did. And now we're ready to remove our stock H-pipe. We can start the assembly of our X-pipe now. We're gonna install the last piece of the X-pipe now. Now that we've got our X-pipe mocked up in place, we can go through and start to tighten all our clamps now. All right. One of the last things we're gonna do under here is put our O2 sensors back in. I chose to do it somewhat last. You guys can put these in before you install your X-pipe. It's all up to you. All right. Now, we're gonna plug it in. All right. We've got a few things to wrap up here. This is the K-member support bar. That can go back on after this, we can put our K-member support brace back up and that's gonna wrap things up. Loosening that up, we're using a 15-millimeter socket here to tighten these down. All right, guys. That's gonna wrap up our review and install. Be sure to check out more at

    Product Information

    Features, Description, Reviews, Q&A, Specs & Installation


    • Required for Kooks Long Tube Headers
    • Improves Exhaust Flow and Sound
    • Raspy Race Car Growl
    • High Flow Catalytic Converters Included
    • 3" to 2.75" Tubing
    • Mandrel-Bent 304 Stainless Steel Tubing
    • Not Intended to be Used with Forced Induction Applications
    • Fits 2011-2014 GT Mustangs


    Increase Performance. Add even more horsepower and torque to the rear wheels of your 5.0 Coyote Mustang with a Kooks Catted Shorty X-pipe. The Kooks Catted X-pipe features high flow race catalytic converters to increase overall performance. This Kooks X-pipe is specifically designed to be used with Kooks Long Tube Headers.

    Race Car Growl.
    This free flowing Kooks X-pipe for the 2011-2014 GT Mustangs not only increases power, but it also adds a crisp raspy, race car growl to the sound of your exhaust with its modern "X" crossover pipe design.

    Quality Construction. Manufactured from 3" diameter mandrel bent 304 stainless steel tubing, Kooks X-pipes feature a merged "X" crossover for superior exhaust flow.

    This Kooks Shorty Catted X-Pipe is specifically designed to fit the 2011-2014 5.0L GT Mustangs with Kooks Long-Tube Headers installed. The step down to a 2.75" outlet allows for use of the OEM exhaust. 

    CA Residents: WARNING: Cancer and Reproductive Harm -

    Installation & What's in the Box

    Installation Info

    What's in the Box

    • (1) X-pipe
    • (2) catted down pipes
    • (2) Clamps

    Tech Specs

    Mid Pipe Specifications
    Style Mid Pipe: Shorty "X" Type Headers Required: Long Tube
    Piping Material: 304 Stainless Steel Piping Size: 3"
    Catalytic Converter: "Yes" Fitment: 2011-2014 5.0 GT Mustangs

    Customer Reviews (19)

      Questions & Answers

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