Borla ATAK vs Corsa Xtreme vs Roush: Picking a Cat-Back for the S550 Mustang GT

This is the most-argued exhaust decision in the Mustang world, and most of the arguing happens without anyone hearing the systems back to back on the same generation of car. We have clips of all three on 2018–2022 GTs, so let's do it properly.

A quick scope note: everything here is about the S550 GT, 2018 through 2022 — the facelift 5.0 with the 10-speed auto or the MT82 manual. If you're on a 2015–2017 or an S650, part numbers and behaviour differ, and you should check fitment for your exact year rather than assuming it carries over.

Before anything else: does your car have active exhaust?

This is the single most common ordering mistake on the S550, and it's expensive to get wrong.

Ford offered a factory active (valved) exhaust on the GT. If your car has it, the quad tips at the back are fed through electrically actuated valves, and the car's software opens and closes them based on drive mode. An aftermarket cat-back for an active-exhaust car has to include its own valves and plug into the factory actuators — which is why Borla sells the ATAK cat-back with valves as a distinct part from the non-valved version, and why Corsa now lists separate "Valved" systems that, in their words, require "use of the factory active exhaust module during installation."

Fit a non-valved system to an active-exhaust car and best case you lose the quiet mode; worst case you're chasing an unhappy module. Fit a valved system to a car without the hardware and you've paid for actuators you can't drive.

Check the car, not the brochure. Look under the rear bumper for actuator motors on the mufflers, or check whether your drive-mode menu has a separate Exhaust Mode setting with Quiet / Normal / Sport / Track options. If it does, you need the valved version.

Borla ATAK

ATAK stands for Acoustically-Tuned Applied Kinetics. It's the loudest of Borla's three standard sound levels — Touring is mildest, S-Type sits in the middle, ATAK sits at the top. Borla builds it as a straight-through, multi-core design rather than a chambered muffler, and tunes the core geometry per application.

What owners consistently report on the S550: it's the deeper of the two big names, with more snarl and more presence inside the car. Threads on Mustang6G and the comparison writeup at AmericanMuscle both land in the same place — Borla is the more aggressive, lower-pitched, more "threatening" note, and it's the one you hear more of from the driver's seat.

That matters more than it sounds. A system that's loud outside and calm inside is a very different ownership experience from one that's the reverse, and the ATAK leans toward the latter.

Hear it: 2019 Mustang GT, Borla ATAK cat-back with valves. There's also a 2018 GT on ATAK in the gallery if you want a second reference point on the earlier facelift year.

Corsa 3" Xtreme

Corsa's range runs Touring, Sport, Xtreme — and unlike Borla, the escalation is partly achieved by removing packed material rather than only by changing core design. Corsa's own description of Xtreme is "the most aggressive option under acceleration while maintaining a drone free at cruise."

The drone-free part is Corsa's RSC technology, which they describe as using "specific geometry to reverse 180 degrees out of phase" to remove low-frequency waves. Corsa applies it across all three sound levels, which is why an Xtreme can be genuinely loud on throttle without punishing you at 70 mph.

The character difference versus Borla is consistent in owner reports: Corsa is smoother and higher-pitched, Borla is deeper. Because the Corsa's energy is higher up the frequency range, it often reads louder from outside the car while being calmer inside. Several S550 owners describe exactly that split in the Mustang6G comparison threads.

The version we have clips of is the 3" Xtreme cat-back, dual rear exit, with 4" black PVD Pro-Series tips. Hear it: 2020 Mustang GT, Corsa 3" Xtreme. We have five 2018 clips of this exact system plus 2019, 2020 and 2021 cars, so you can check whether it changes across model years. It largely doesn't — which is itself useful information.

Roush

Roush is the outlier here, and it's the one people skip because it isn't part of the Borla-versus-Corsa argument.

Tonally it's the most traditionally American of the three: fuller at idle, less rasp than the ATAK develops at the top end, and a note that owners tend to describe as muscle-car rather than sports-car. It's the choice if what you want is the sound a Mustang has in your head rather than the loudest possible version of it.

The trade-off shows up at cruise. Roush does not market a proprietary drone-cancelling technology the way Corsa and AWE do, and owner reports of low-RPM drone in top gear are more common for the Roush than for the other two — the classic complaint is a deep tone when you lean on the throttle around 2,000 RPM in sixth. Discussion at SVTPerformance and Mustang Evolution covers this in detail.

For a V8 at 2,000 RPM, that's a 133 Hz pressure wave in the cabin — right in the band a car body is worst at absorbing. If your commute is mostly highway in top gear, weight this heavily. If you drive in town, it may never bother you.

Hear it: 2019 Mustang GT, Roush cat-back. We have 2018 through 2021 cars on this system.

So which one

Honestly: all three are well-built stainless systems from established manufacturers, all three fit, and none of them is a mistake. The decision is about character and about your commute, not about quality.

Choose Borla ATAK if you want the deepest, most aggressive note and you want to hear it from the driver's seat. It's the most dramatic of the three. If you're on a car with factory active exhaust, the valved version gives you a genuine quiet mode, which makes the aggression much easier to live with.

Choose Corsa Xtreme if you want maximum volume and drama with the least penalty at cruise. RSC is the most aggressive anti-drone engineering in this group, and the higher-pitched tone means what you hear inside the car is less fatiguing at speed. It's the safest pick for someone with a long highway commute who still wants loud.

Choose Roush if you want classic muscle-car tone over outright aggression, and you're not doing 300-mile highway days. It's the least shouty of the three in character while still being clearly aftermarket.

Do this before you order

Play the three clips back to back, on headphones, on the closest model year to yours. Do it twice — once listening for tone, once listening specifically for the low end at steady throttle.

Then check three things on the product page for your car:

  1. Valved or non-valved, matched to what your car actually has.
  2. Your exact model year, because Ford changed exhaust hardware across the S550 run.
  3. Tip diameter and finish, because it's the part you'll look at every day and the part that's hardest to change later.

Everything else — the hangers, the clamps, the stainless grade — is table stakes at this level.

Browse the full sound clip gallery to hear other systems on the S550, or go straight to Borla and Corsa to see what's currently available for your year.

Sources

Back to blog