Flowmaster Cat-Back Exhaust System American Thunder 2-1/4" with Polished Oval Tips Stainless Steel Focus ST 2013-2015

Flowmaster: 817637
MSRP: $795.55
CJ's Low Price:
1432857600 4542
Pick up this item to go along with your new Cat-Back Kit!
CJ's Low Price:
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CBF56 CBF56_1 CBF56_2 Play Flowmaster Cat-Back Exhaust System American Thunder 2-1/4 Play Flowmaster Cat-Back Exhaust System American Thunder 2-1/4 Play Flowmaster Cat-Back Exhaust System American Thunder 2-1/4

Product Description

Flowmaster American Thunder 2-1/4" Stainless Steel Cat-Back Exhaust System with Polished Oval Tips for 2013, 2014 and 2015 Focus ST.

Flowmaster's cat-back system features 2-1/4" mandrel bent stainless steel tubing. A tuned resonator style muffler delivers a moderate to aggressive exhaust sound. All parts are welded together and built to last. Dual polished oval 3-1/4"x3-3/4" tips exit the center of the rear bumper. Flowmaster's cat-back is dyno tuned for maximum performance. Get the most power out of your 2.0L turbocharged engine with Flowmaster's exhaust system.

The American Thunder cat-back is perfect for the person looking for moderate to aggressive sound levels with all of the performance benefits that you would expect from Flowmaster. Flowmaster's cat-back bolts in place of your original exhaust. Just like all Flowmaster products, this exhaust system features high quality components and construction for long lasting life. Made in the USA!

So what are you waiting for? Upgrade the look, feel and overall performance of your 2013, 2014 or 2015 Focus ST with Flowmaster's American Thunder 2-1/4" Stainless Steel Cat-Back Exhaust System with Polished Oval Tips from CJ Pony Parts today!


Mustang Applications

This product will fit the following Ford Mustang years:

Product Reviews

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Flowmaster Cat-Back Exhaust System American Thunder 2-1/4" with Polished Oval Tips Stainless Steel Focus ST 2013-2015 is rated 5.0 out of 5 by 1.
Rated 5 out of 5 by from Sounds amazing!!! Easy installation looks great sounds amazing very impressed.
Date published: 2015-01-09
  • 2015-05-29T10:08CST
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Product Questions


I just recently installed this exhaust and after running a few times I got a check engine light and checked the fault  it was for turbo pressure. Have you heard of this exhaust causing any problems with that?

Asked by: shawn1994
No, we've never heard of those issues.
Answered by: CJ Pony Parts
Date published: 2015-05-11

Will this exhaust pass California emission laws?

Asked by: Jacobst4
We don't keep track of all of the parts approved for California, as it is a constantly changing list. We encourage you to check the list of official approved CARB parts here: http://www.arb.ca.gov/msprog/aftermkt/devices/amquery.php.
Answered by: CJ Pony Parts
Date published: 2015-04-29


Asked by: justcurious
Watch the video to get a sound clip, which will give you a good idea of how it's going to sound on your Focus ST.
Answered by: CJ Pony Parts
Date published: 2015-04-21

Will this system fit on a 2015 Focus ST?

Asked by: ECOB1
Update: It has been confirmed to fit the 2015 ST.
Answered by: CJ Pony Parts
Date published: 2015-04-03

Hey I just have a quick question. Is it possible to swap the tips to the stock one?

Asked by: Meehow
As long as the diameter is the same, yes.
Answered by: CJ Pony Parts
Date published: 2015-03-17

Is this american Thunder catback made out of 304 stainless or 409?

Asked by: Jeffy_2010
It's made from 409.
Answered by: CJ Pony Parts
Date published: 2015-03-16

I am looking for an exhaust kit that is louder than stock but not so much to get me into trouble with the law (or my dad). I love the sound of this cat-back kit, is it too loud?

Asked by: Danilion
That's more in the eye (or ear) of the beholder. Most of our Focus ST exhausts have videos on them, which will include sound clips, so you can listen to them and make the choice for yourself.
Answered by: CJ Pony Parts
Date published: 2015-03-11
  • 2015-05-29T11:43CST
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Product Video

By Bill Tumas: Obviously, we're Mustang enthusiasts here at CJ's, but we're actually fans of all Ford's high-performance vehicles, including the SVT Raptor, Taurus SHO, and the latest creation, the Focus ST. With its 252 horsepower turbocharged 2 liter, Recaro seats, and high-performance breaks and suspension, this is one hot hatchback. Today, we're going to add some performance and sound to our Focus by installing this Flowmaster exhaust system.

The system is designed by Flowmaster specifically for the Focus ST and as part of their American Thunder series. It's fully stainless steel with all mandrel pipes leading through a high flow muffler, and finishing off with a pair of double walled rolled stainless steel tips. The center exit exhaust is one of the unique features found on the Focus ST. It doesn't sound bad for a stock system. We're sure the Flowmaster's going to give us improvement in sound as well as performance, so let's get started.

For this installation, you'll need a jack and jack stands or a lift and pole jack, Sawzall, 1/4 inch ratchet, 3/8 deep socket, 3/8 ratchet, we suggest a 3/8 impact gun, 5/8 shallow socket, 10 mm socket, 15 mm socket, 11/16 wrench, 15 mm wrench, exhaust gasket tool, and safety glasses.

Once you have the car off the ground, we're going to remove the stock system. In this case, the stock system is welded front to back. The only way to remove it is going to be to cut it right here in the middle so you can separate the front and the back. Now we're going to spray some penetrating lubricant on the bolts in the front, as well as all the hangers to make them easier to take off. We'll start removing the front of the exhaust system by first removing this brace from the floor.

There are studs going from this side through and there's retaining nuts on the other side. Either come in with a socket over the top, in our case, we need a ratchet and wrench, just get them right here from the front. Now we'll separate the factory muffler from the flex pipe. You'll want to remove the gasket here as it is reused with the new system. Now remove the pipe from the hanger. Then, remove the stock muffler. Here you can see the stock muffler verses the Flowmaster muffler we're installing. Obviously there's a fairly large restriction there we're going to be taking out with the Flowmaster system.

Before we move on to the muffler and the tip, and we didn't get the hanger for the tailpipe. It's located right on top here. Now, we're going to remove the muffler and the tip assembly. Start by taking off the hanger on the driver's side. Next we'll take the passenger side one off. Now, lower this down. Push the pipe through the opening. Now, we'll install the new bolts that came with the kit. Install the gasket. Put it up into place. We have our jack to hold it for us. Now, we'll install the washers and the nuts on the other side. At this point, hand tight is fine and move on to the rest of the system.

Next, we'll grab the S-shaped pipe and one of our supplied clamps. Install that in the factory hanger. Now we'll tighten up the clamp, push to the edge where the pipes connect. Just get it snug. We still want to be able to adjust it. Grab the tailpipe. Just want to feed it up over. Fit it to the front and then slide it over so you can get the original hanger hooked up to it. Once again, we're going to tighten the clamp. Just get it snug, not all the way tight. Going to put a clamp on the tailpipe section here. Start by hanging the passenger side first. You're going to connect it to the rest of the tailpipe. Slide it on the driver's side. Get it centered as best you can.

Now, we start tightening to the rest of the system. I'll start by tightening the bolts at the front here. You want to hold it up while you tighten it. You can do this with a ratchet, but an impact makes it a lot easier. You want to check the clearances make sure nothing's touching. Then we can move onto the exhaust tips. Slide them over the edge. Want to get them centered and equal distant in the opening. Then we can tighten them down.

Now, we have everything fitted and tightened down, we can reinstall the front brace. Installation's finished. Now, that we're done the installation, let's fire it up and see how it sounds. Just like we expected, a much more aggressive sound. You can even hear the turbo through the exhaust now. Thanks to Flowmaster our Focus ST now sounds as aggressive as it looks. Removing those two large factory mufflers freed up some horsepower and also shaved some weight at the same time. Installation should take you around two hours. You'll be back on the road in no time.

For more Focus ST installation videos, make sure you subscribe to our YouTube channel.