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2015 EcoBoost Build

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Table of Contents
  1. Build Video
  2. Parts List
  3. Video Transcript

Take a look as we take AM Enthusiast, Heather's stock 2015 EcoBoost and install a ton of aftermarket engine modifications. We install a C&L Cold Air Intake, Borla Off-Road Downpipe, Borla ATAK Catback Exhaust, and COBB Accessport V3 Tune to put this EcoBoost engine to the test. Watch to see what horsepower gains we get after running it on the dyno.

AM Enthusiast Heather's 2015 EcoBoost Build

Hey, guys. Today we're gonna show you exactly how well the 2.3 EcoBoost engine reacts to aftermarket modifications. And with this car, there is no better place to start than with the turbo and opening up some airflow around it. So, we're gonna throw on a new exhaust system from the turbo back along with a cold air intake, and we'll wrap it all up with a custom tune to dial it all in and push some more boost.

This EcoBoost was still working with the factory airbox when it came to us so one of the first things that we did here is swap that out. It's worth mentioning that the factory airbox for the S550 isn't a bad intake setup. It's pretty efficient and functions well. But as you start to mod the car, it'll become restrictive. And that's something that we wanted to make sure that we didn't encounter, and so we chose the C&L intake because if you're looking for performance gains it has one of the best designs on the market. The key to this design is going to be this airbox. It's an enclosed airbox, one of the only on the market and it has a removable lid so you can get to your filter easily. The enclosed airbox is also going to protect the filter from elements inside the engine compartment and, more importantly, it's going to help keep warm air from inside the compartment from being used by the intake, and this is a technique that works. We saw some low intake air temps on the dyno and this leads me to another cool thing about the housing and that taps into the factory cold air duct, which brings cool air in from the grille instead of using warm engine compartment air. This is a really nice feature in my opinion and it gives this intake a benefit that you don't see for many other aftermarket intakes for the S550 EcoBoost. A few other real quick notes about this intake. It's got a classic reusable air filter and can be cleaned and re-installed and it's also got a nice sized intake tube which is important if you're looking for the most gains possible. Any gains over the stock setup are going to be coming from the intakes with larger filters and intake tubes.

Of course, that's not all we did with the car, but we've got to get the car in the air to show you where we did some of the more serious modding. In the world of turbos, one of the first and most beneficial power mods that you can do is get a new downpipe, so that's exactly what we did. The factory downpipe on the EcoBoost is pretty restrictive so this downpipe is going to be for those people that are looking for less restriction, which ultimately means some improvements in performance. An aftermarket downpipe can offer a big improvement in performance because it helps the airflow of the turbo where you pretty much want things as unrestricted as possible so you can spool the turbo more quickly, which is where your gains will come from.

Two big things about this downpipe. It's a three-inch downpipe which is an upgrade over the stock downpipe and it's one of the only three-inch downpipes that are available right now. The other thing is this is a cat-less or off-road downpipe, so we're talking even less restriction. It's a stainless steel downpipe as well and another great thing about this downpipe is that it gives you an option when it comes to the rest of your exhaust. Borla includes an adapter for this downpipe so you can still use a stock exhaust if you want, but of course, we didn't wanna do that here. The cat-back we've got on here today is the Borla ATAK cat-back and that's actually a two and a quarter inch system. One thing I will say is that it's great to see a three-inch downpipe that'll still work with a two and a quarter inch system because you can still get the max benefits from the three-inch downpipe. Now, the Borla ATAK is not only a high-quality system being a full 304 stainless steel and great fitting, but it's also one of the loudest and most aggressive systems for the turbo four-cylinder Mustang. I'm talking a ton of volume and a ton of turbo noise.

Now, all of these exhaust mods definitely made a huge difference in sound, even that downpipe. Even though the main idea behind an aftermarket downpipe is to help give the turbo unhindered airflow, an aftermarket downpipe is also gonna give you more sound too. And since this particular downpipe is an off-road or uncatted downpipe, you can expect an even louder result like the sound you just heard. So, while the combo of these mods makes a beastly sounding turbo four-cylinder, I'd actually like to see what exactly it all equates to on the dyno and what we're looking at in terms of power and torque gains. But before we do that, we need one more thing that's going to tie all of this together for us, and that's going to be a Cobb Accessport. We went with the Cobb Accessport for the fast downloads and the on the fly adjustability that it offers. But enough about ports, let's get this thing on the dyno.

Of course, we ran the car before installing any mods so we could have some baseline numbers to compare to, and that baseline run gave us numbers of 245 horsepower and 277 foot-pounds of torque at the rear wheels. With all of our parts installed and with a Cobb Accessport tune, the car made 311 horsepower and 360 foot-pounds of torque making for a peak gain of 66 horsepower and 83 foot-pounds of torque. As with any dyno result, peak gains are always nice to know, but the real thing I look for is differences throughout the curve. The curve is going to show you the changes that were made in your driving RPMs and these are the things that you're actually going to notice performance-wise when you're driving. So, throughout the curve, we're seeing gains here 113 horsepower in the 6,400 RPM range and 96 foot-pounds of torque right in that same range. Now, these are some pretty big curve gains, more than 100 horsepower and almost 100 foot-pounds of torque in the curve. This graph tells me that we should have a totally different feeling car to drive. So, with all of that being said, I really just wanna drive this thing, so let's take it out for some road time.

All right. So, first thing to do with [inaudible 00:05:37] is obviously going to be our new exhaust tone. It's very loud. Very loud, and you guys already heard that in the sound clips. Like I mentioned, it's definitely that raw turbo four-cylinder sound and that's undeniable. The Borla three-inch downpipe, like I said, uncatted with the Borla ATAK which is the loudest cat-back, I mean turbo four-cylinder all the way there, especially when you start getting into upper RPMs. The one good thing about it, it's obviously not gonna be for everyone. It's definitely not a sound for everyone but if you're looking for lots of turbo noise, a lot of sound, a lot of volume, then this is where your setup is going to be. Everyone is gonna hear you coming, you can hear every single shift, you can't really hide. So, I hope you're a good driver.

So, if we wanna test out drone at cruising RPMs, we're just over 2,000 RPM right now, we're at 2205, we're not quite at 2500 yet. You can definitely hear that there's an aftermarket system on this car, but when you're driving down the highway, I wouldn't say that this is anything that your eardrums are gonna be bleeding. You're not gonna be terribly upset at the end of a long trip with this car. You can hear that there's aftermarket exhaust on it like I said, but it's not a crazy loud drone. If we go up to 2500 RPM, it does. It does drone out a little bit, you can hear it right there. It's a little bit more droney at 2500 RPM. But I'm really surprised that it's not any worse, especially considering how loud the system is and the type of volume that it has.

Another thing that I did notice is that there is pretty decent amount of crackle on decel with this car when you're off-throttle, especially if you're above 3000 RPM and you go to a downshift, there's a little bit of popping. For people that are looking for that, it's actually a nice feature. It just adds a little bit something more to the system.

One thing that I'm really interested to see and I'm really happy about is the tune. This tune had great results, a ton of power and a ton of torque gains onto the curve. And I can feel a huge difference already in the car. It's one of the most exciting things. You buy a couple mods, you spend a little bit of money and you get a tuner, and it ties everything together. It's just so much of a difference in drivability in this car. From factory after 5,000 RPM, this thing just fell on its face. And we saw on the dyno graph that it still falls, there's definitely a curve down, but it's not nearly what it was from factory. And what I can tell you right away, just from driving in some of the lower RPMs, is that this thing, you can definitely feel the huge low-end torque gain. It drives so much better. Honestly, it really wasn't much fun to drive before. It fell on its face and it was a little bit disappointing honestly for me, but now, you wanna just lay into it a little bit.

Yeah. You can definitely hear turbo spool from inside the car, especially in the low RPMs. You lose it a little bit from inside the car because the system is just so loud. And even just laying into the car, that was a little test right there. Just laying into the car from lower RPMs and seeing how it goes through the RPMs, that's a test of the tune and that felt great to me. The car just pulled 2,500 right now, lay into it. It actually sits you back in the scene a little bit, which was something that it definitely didn't do before. So, it's definitely a little bit more fun to drive. Even at idle, this thing is a lot louder. It's just louder all the way around.

The tune is definitely nice. It definitely makes you wanna go through those gears a little bit faster. Like I said, throughout the curve, over 100 horsepower and almost 100 foot-pounds of torque. That's something that you're definitely gonna notice. There's no not noticing that. So, the combination of this downpipe and the cat-back, I can hear it right now because I'm actually just driving around in a parking lot. You actually get some of that turbo gurgle that you hear a lot of times with turbo cars that have more free exhaust. There's a little bit of gurgle to it right before the turbo starts spooling. So, like I said, if you're really interested in hearing a lot more of that turbo noise, then this exhaust setup is definitely gonna be your good option. It's going to be your go-to option.

All right. Let's try to jump on a little bit. Do just a little more. You can definitely feel over 5,000 RPM. There is a little drop-off, but to be completely honest with you, the car does pull before it starts to hit that drop-off. You can feel the turbo going to work. It drives a whole lot better overall. So, this definitely isn't a sound or a setup that's going to be for everyone out there on the market. It's loud, it's definitely in your face, and it's definitely that raw turbo four-cylinder sound. Really what we started out to do here, at the end of the day, was see how these cars react to some mild bolt-ons and a mild tune. And I think that this was a great test of this car's ability to rapidly pick up power and torque all throughout the curve, low-end, top-end with just pretty much mild stuff. This is all stuff that novice mechanics can do in their garage, in their driveway. This isn't serious stuff that you have to go to a garage for. So, I think ultimately, at the end of the day, it's great to see that these cars respond so well to just a few mods that really only take a few hours to do and you get a great, fun result. Thing definitely gets up to speed a lot quicker now after the fact, which is really nice because it's effortless. It feels effortless now whereas before it'd be like, "All right. Let's get up to 50 miles an hour. Come on, girlfriend." But now it's pretty effortless and it's's great.

All right. So, that's gonna wrap up this EcoBoost build. Overall, I'd say I'm really happy with all the gains that we saw from a few minor bolt-on modifications paired with a tune. I hope you guys enjoy the video. And as always, for all things Mustang, keep it right here at