Christopher Campbell Technical Editor
April 3, 2015

There is a checklist of parts that every enthusiast looks into as soon as a bit of the new car freshness wears off on their Mustang. Right at the top of the list are a cold air intake and a new tune. It’s not that Ford can’t design an airbox that flows as well as any aftermarket part, or a tune that extracts every last iota of horsepower and torque; it’s that Ford has to contend with these and so many other issues simultaneously.

There are of course the expected hurdles set up by the EPA, not to mention the California Air Resources Board, for emissions and fuel economy, but as much as this makes us roll our eyes, another factor is just as big. Hard as it is to believe, a large portion of the population purchases Mustangs and leaves them stock! They don’t seek out parts to increase acceleration, and they certainly aren’t willing to have a louder engine with increased octane requirements and potentially lower mileage (because it’s fun and you can’t keep your foot out of it) in order to get more acceleration. We probably couldn’t be friends with those people.

For the rest of us Mustangs mavens, the aftermarket is always there to provide us with the parts we wish were stock equipment. The totally new 2015 S550 Mustang is just barely available, but performance parts are already turning up. Thankfully, pure enthusiast companies like JLT Performance and SCT Performance have no strings holding them back; their focus is solely on power production. That’s why when we heard that their new cold air kit and programmer for the S550 was available, we touched base with them immediately to put it to the test. Let’s be real—we know that all of you who end up with a 2015 in your driveway will be pondering which parts to buy first.

Our buddy Eddie Rios at Addiction Motorsports had just taken delivery of his 2015, so we tapped him to be our test mule. Rios has some pretty serious plans for his S550, so you’ll be seeing quite a bit more of it in future stories. For now, we were impressed with how much bang-for-the-buck this 30-minute install offered up.

1. Here is JLT’s replacement for the stock intake track. All of the parts are direct bolt-in to stock locations, but instead of a small rectangular filter we will have an 8-inch-long conical filter within a large-capacity airbox. We were impressed with the OEM-level quality of the parts.

2. More airflow potential requires a new tune to really extract the benefits. JLT loads its custom tune on an SCT handheld programmer for easy reflashing of the ECU.

3. As much as the exterior has changed, underhood the intake system is still familiar to anyone who has wrenched on a Coyote-powered Mustang before. First on the agenda is to remove the engine cover by pulling up firmly to create easier access to the throttle body.

4. A band clamp holds the intake tube to the throttle body. Loosen it up so that the boot slides easily from the throttle body.

5. On the inside of the intake tube’s curve, near the throttle-body, three connections need to be removed. Two are quick-release, while the third (for the sound tube) uses a clamp. The easiest way to remove the sound tube is to squeeze the sides of the clamp together with pliers while pulling on the tube.

6. After pulling the MAF plug from the harness, pry the harness clip away from the stock housing. A door panel tool works well for this.

7. Flip open the clamps on the airbox lid. The intake tube and lid will come out as a complete unit.

8. Just one last 10mm bolt is holding the main body of the airbox in place. Remove this one, and it’s time to pull it out.

9. The airbox has a snorkel that extends forward into the grille, so to remove it, lift from the rear first and pull rearward until the snorkel clears the core support.

10. Coyote-powered Mustangs have a sound tube to pipe the intake into the cabin, but paradoxically the airbox features multiple mufflers to tone down the sound. Despite its size and unnecessary complexity, it is a fairly light assembly, at least.

11. JLT’s airbox utilizes the same cool air path behind the grille as the factory unit. The tube that will mate to the original inlet is a separate piece, and a tight fit, so it’s best to slide it in prior to placing the box into the car.

12. Two grommets need to be removed from the original box and transferred over to the JLT box. This two-piece one with an inner sleeve is the grommet from the bolt that holds the box to the inner fender.

13. Right next to the bolt is this grommet that a locating post on the airbox will simply press-fit into.

14. With the grommets installed, the airbox is dropped into place. The JLT box is significantly larger than the factory one, so it’s necessary to slide the air inlet tube inside the airbox until it is seated completely inside.

15. The air inlet tube then slides forward and connects with the factory duct behind the grille.

16. A new sleeve and clamps to mate to the throttle body to the intake tube are provided with the JLT kit.

17. The quick-connect fittings slide onto the JLT intake tube and fit like factory. We can’t imagine who would use it, but a plug is provided if you would like to cap off the sound tube.

18. The new conical air filter is not only reusable but will provide much higher flow capability due to its increased surface area. It is definitely a win-win situation.

19. The last step to the underhood portion is to install the MAF sensor into the JLT intake tube with new hardware. Plug the harness into it, and we’re ready to tune!

20. We love the complete underhood install since it has a clean factory-equipped look. This whole swap took us about an hour, including taking photos, so it’s basically a 30-minute deal for everyone else.

21. Here’s where we make the most of that newfound airflow! The SCT tuner comes preloaded with JLT’s recommended tune for an otherwise stock car. This part requires more patience than the underhood install because the tuner makes a backup of the original tune and then installs the new tune.

22. Check out the before-and-after dyno run at Addiction Motorsports. Horsepower and torque are up all the way through the curve with peak numbers of 372.05 hp and 355.90 lb-ft of torque. That’s a 12.36 hp and 6.25 lb-ft of torque to the wheels, which will definitely be noticeable. Plus, there is a throatier sound from the intake without all those mufflers. Sound and power—there’s no downside here!