If you're looking to swap out your stock frs exhaust system, you probably already know that the factory setup is a bit too quiet for a car that looks this good. The Scion FRS (along with its siblings, the BRZ and 86) is a fantastic driver's car, but from the factory, it sounds more like a vacuum cleaner than a sports car. Upgrading the exhaust is usually the very first thing owners do, and for good reason. It changes the entire personality of the car, giving you that feedback you need when you're rev-matching a downshift or hitting the redline on a backroad.
But before you go out and buy the loudest pipe you can find, there's a lot to consider. It's not just about making noise; it's about the tone, the weight savings, and how it fits into your overall build goals.
Why Bother Replacing the Stock Setup?
The stock frs exhaust system was designed to meet strict noise regulations and keep the general public happy. It's heavy, it's restrictive, and it hides the unique character of the 2.0L boxer engine. When you switch to an aftermarket setup, you're usually doing it for three main reasons: sound, weight, and aesthetics.
First, let's talk about the weight. The OEM muffler on an FRS is a massive, suitcase-sized hunk of metal that hangs right off the back. It's surprisingly heavy. Most aftermarket cat-back systems, especially those made from high-quality stainless steel or titanium, can shave off 10 to 30 pounds. On a car that only weighs about 2,800 pounds, losing that much weight off the very rear of the car is actually something you can feel in the corners.
Then there's the sound. The flat-four engine has a very distinct rhythm. Depending on the setup you choose, you can either accentuate that "boxer rumble" or go for a high-pitched, race-inspired scream. Plus, a more open exhaust helps a bit with throttle response, making the car feel just a little more "alive" when you step on it.
Cat-Back vs. Axle-Back: What's the Difference?
When you start shopping, you'll see these two terms everywhere. If you're new to the car scene, it can be a bit confusing.
An axle-back system is exactly what it sounds like. It's the portion of the exhaust from the rear axle to the tips. Basically, you're just replacing the muffler and the exit pipes. This is the way to go if you're on a budget and strictly want a better sound without worrying about performance gains. It's easy to install and usually the cheapest option.
A cat-back system, however, replaces everything from the secondary catalytic converter back to the tips. This includes the mid-pipe (the long pipe that runs under the middle of the car) and the muffler assembly. This is the most popular choice for the FRS because it replaces more of the restrictive factory piping. It offers a more complete sound profile and a bit more of a power bump compared to just an axle-back. If you're serious about your frs exhaust system upgrade, a cat-back is usually the "correct" starting point.
Single Exit vs. Dual Exit
This is one of the biggest debates in the FRS community. The car comes from the factory with a dual-exit exhaust, meaning there's a tip on the left and a tip on the right. Because of this, the rear bumper has two cutouts.
Dual exit systems look balanced and "OEM-plus." They fill out those bumper cutouts perfectly and usually offer a deeper, more refined tone. Most owners stick with dual exits because they don't want a "hole" on one side of their bumper.
Single exit systems, on the other hand, are all about performance and that "JDM" look. By running only one pipe to one side, you save a massive amount of weight. We're talking a significant difference. However, it leaves one of your bumper cutouts empty, which some people hate. You can buy "bumper caps" to cover the empty hole, but it's definitely a more aggressive, track-focused look. If you're building a time-attack car or just want the loudest, lightest setup possible, a single exit is the way to go.
Dealing with the Infamous Drone
One thing nobody tells you until you've already spent $800 is that some exhausts "drone." Drone is that annoying, low-frequency humming sound that vibrates through the cabin when you're cruising at a constant speed on the highway. It can turn a fun car into a headache-inducing nightmare on long road trips.
If your FRS is a daily driver, you'll want to look for an frs exhaust system that includes a resonator in the mid-pipe. Resonators are designed to cancel out those specific annoying frequencies without muffling the "good" sounds. Brands that focus on "touring" setups usually do a great job of keeping the car quiet at 70 mph while still sounding mean when you open it up.
The Role of the Header
You can't talk about an frs exhaust system without mentioning the headers. If you really want to change the sound and fix the car's famous "torque dip" (that annoying loss of power around 4,000 RPM), the header is where the magic happens.
There are two main types: Equal Length (EL) and Unequal Length (UEL). * UEL Headers: These give you that classic Subaru rumble. Because the exhaust pulses reach the collector at different times, it creates that "thump-thump-thump" sound. Most FRS owners go this route because it sounds incredible. * EL Headers: These are better for pure performance. They provide a smoother flow and usually a bit more top-end power, but the car will sound more like a traditional four-cylinder (think Honda or European sports cars).
Just keep in mind that changing the header usually requires a tune (like an OpenFlash Tablet or EcuTek) to make sure the engine runs safely and actually gains power.
Materials Matter: Stainless vs. Titanium
Most exhausts you'll find are made of T304 Stainless Steel. It's the gold standard because it's durable, resists rust well, and isn't insanely expensive. It'll probably last longer than the car itself.
If you have money to burn, you might look at Titanium. Titanium systems are incredibly light—you can literally pick up a whole cat-back with two fingers. They also have a very distinct, "metallic" sound and the tips often turn a beautiful blue color from the heat. The downside? They are significantly more expensive and can be a bit more prone to cracking over many years if the welds aren't perfect.
Installation: Can You Do It Yourself?
One of the best things about the frs exhaust system is how easy it is to work on. Unlike some cars where you have to drop the whole subframe just to change a muffler, the FRS is very straightforward. If you have a set of jack stands, a socket set, and some WD-40 (to help slide the rubber hangers off), you can swap a cat-back in your driveway in about an hour or two.
The only tricky part is usually the bolts connecting the mid-pipe to the front pipe. Those can get pretty rusty and stubborn. My advice? Spray them with penetrating oil the night before you plan to do the job. It'll save you a lot of swearing and potentially a broken bolt.
Final Thoughts
At the end of the day, the "best" frs exhaust system is the one that fits your lifestyle. If you just want to hear the engine a bit more while driving to work, a resonated dual-exit cat-back is a safe bet. If you're building a weekend canyon car and want everyone to hear you coming, a UEL header paired with a single-exit pipe will give you that raw, aggressive personality the car deserves.
Take your time, watch plenty of YouTube "sound clip" videos (though they never quite do it justice), and think about whether you can live with the volume on a daily basis. Once you get that perfect tone dialed in, you'll find yourself taking the long way home every single time just to hear the car sing.