Allow Your 5.0L Coyote To Breathe!
There’s no doubt that the factory 435 horsepower 5.0L Coyote V8 found in the 2015-2017 Mustang GT is one impressive piece of engineering. Factoring in roughly 15% for drivetrain loss, you’re looking at about 370 horsepower to the wheels! Taking into account that before 2010 the Mustang GT had about 300 horsepower to the crank and even less to the wheels, the GT’s powerhouse has come a long way.
Even so, that 370 whp may not be enough to some Mustang GT owners. And that’s what your friends here at CJ Pony Parts are here for! There are many options when it comes to adding performance modifications to your Mustang in an effort to squeeze some more power out of that modular V8.
After a cold air intake and tune, the next performance modification is usually exhaust. The problem with modifying the exhaust on your Mustang is that there are so many different options -- literally hundreds. That’s great for someone who likes options, but each different type of exhaust system has its own unique sound. Since exhaust is such a subjective mod, we’ll do our best to give you the facts as unbiased as possible, but even we have our favorites!
Picking the right exhaust system for your S550 Mustang GT is important. There are different types of exhaust systems, price points, and combinations that produce different kinds of sounds. An aftermarket exhaust system from manufacturers such as Ford Performance, Magnaflow, AWE, Borla, or MBRP will allow you to let your Mustang’s personality shine the way you want it. So, let’s get to it!
Mustang GT Axle-Back Exhaust
For those on a tight budget, the easiest option that will give you that signature Mustang growl but not break the bank would be an axle-back exhaust system. Unlike the S197 platform, the new S550 platform will require cutting for proper installation, but it isn’t too difficult of a job!
The number one benefit to picking up an axle-back exhaust is the change in exhaust volume, tone, and depth over the quiet, restrictive factory mufflers. For axle-back exhaust, there will be minimal power increases.
When you’re getting ready to purchase your new axle-back exhaust kit, be sure to review the manufacturer's instructions for the proper area to cut your factory exhaust system. And remember, you can always cut more off, but it’s much, much more difficult to weld more pipe back on!
Mustang GT Cat-Back Exhaust
For most Mustang owners, the go-to option would be a cat-back exhaust. This is a happy medium between price, exhaust note, and performance. Most cat-back kits offer a small boost in power output along with that signature muscle car exhaust note. The problem with the S550 is the factory resonator that hangs in between the catalytic converters and the mufflers. Ford installs a resonator in the factory exhaust system in an effort to cut out certain noise frequencies -- typically highway drone in most cases.
The factory resonator makes for a comfortable and quiet ride, but most enthusiasts didn’t buy a Mustang GT to not be able to hear the exhaust note! That’s why picking up a cat-back exhaust system will give you the most bang for the buck when it comes to increasing power output, exhaust volume, all without hurting your wallet.
Another serious advantage to the cat-back kits are the fact that there is no cutting required for installation, unlike an axle-back exhaust. Simply just un-clamp your factory exhaust in front of the resonator and slide your new cat-back into place!
Headers are for those Mustang owners who purely want an increase in performance, and that’s their number one priority. Due to the high-heat conditions exhaust headers have to endure, high-quality stainless steel and a perfect fit are required, meaning a slightly higher price point. However, the benefits definitely outweigh the price when it comes to a good set of long tube headers!
Long or short tube headers increase exhaust flow where it matters - close to the engine. By removing the restrictive factory catalytic converters and installing wider piping, exhaust gases will be able to escape your Mustang’s engine much quicker. An example of this would be long tube headers, which are especially known for serious power increases at the top of the power band.
Don’t get us wrong, you’ll definitely see a decent increase in how throaty your exhaust note will be after installing a set of headers, especially long tubes. But more times than not, when a Mustang enthusiast is looking for a set of headers, it’s to increase power more than sound due to the higher price point. And that performance increase is definitely worth it!
Headers typically come in two different ways: With catalytic converters (or cats) and off-road (without cats). If you plan on driving your Mustang on the street, like most owners, then you want to pick up a set of headers that come with high-flow catalytic converters. If you are looking for every ounce of power out of your Mustang and plan to only hit the dragstrip or road-course, then a set of headers without cats will do the trick for you.
Is A Tune Required?
Both axle-back and cat-back exhaust systems do not require a tune. This is in part why these two options are so popular. You can add a grumble to the exhaust note and add a couple of horses without interfering with your Mustang’s computer.
However, if you’re looking to pick up a set of long tube headers, it’s strongly recommended that you get a proper tune to support the new system. This is because your O2 sensors will be relocated and will have to adjust to different levels courtesy of the new headers. If you do not get a tune, your engine could run too lean resulting in potentially catastrophic problems. Do the smart thing and get a supporting tune when modifying your factory exhaust manifolds and catalytic converters.
Budget-Friendly: Creating Your Own Cat-Back!
In most cases, there is a more cost-effective option if you don’t want to pay for a full cat-back system but want to get rid of your factory resonator. That would be to pick up an axle-back kit and pair it with a resonator delete mid-pipe.
Depending on which sound you’re going for, you can either get a resonator delete x-pipe or h-pipe. For those that light a high-pitched, raspy European sound, then an x-pipe is for you. An h-pipe is for the enthusiast who enjoys an old-school, deep muscle car sound. More reminiscent of the pushrod 5.0L in the Fox Body Mustang. To learn more about x-pipes vs h-pipes, check out our other tech article.
By creating your own cat-back, you’d cut your factory exhaust halfway through the intermediate pipes for the axle-back kit of your choice and just after the factory resonator to install the resonator delete pipe. It can be a bit more cutting than most are used to, but the result is a cat-back you can call your own for a fraction of the price!
Choosing The Perfect Exhaust For Your Coyote-Powered Mustang
Here at CJ’s, we try to make it as painless as possible with a large variety of exhaust videos at your disposal. That way, you can educate yourself with the right information before pulling the trigger on a new exhaust system for your Mustang. So, be sure to check out your YouTube channel and give us a call when you’re ready to purchase new exhaust for your Mustang GT!