If you own a Subaru BRZ or Toyota 86, you already know the boxer engine’s inherent character is one of the car’s defining traits. While the naturally aspirated FA20 produces respectable power, many enthusiasts find the factory exhaust note too quiet or muted for the driving experience they crave. Upgrading your exhaust system is the single most effective way to transform how the car sounds, adding personality, excitement, and a deeper connection to the road. Whether you want a subtle bump in volume or a full-blown track-ready scream, this guide covers the best exhaust sound modifications available for the Subaru BRZ and Toyota 86, including the technical details that matter.

Understanding the FA20 and Exhaust Acoustics

The Subaru FA20 is a four-cylinder horizontally opposed (boxer) engine. Its unique firing order and symmetrical layout produce a distinct exhaust pulse that, with the right exhaust system, can sound unlike any other four-cylinder. The stock system is designed to meet noise regulations and reduce interior resonance, but it also restricts airflow and dampens the engine’s natural character. The key to unlocking a great exhaust note lies in understanding how each component of the exhaust system alters the sound waves produced by the engine. From the header to the tailpipe, every change influences tone, volume, drone, and performance.

Exhaust System Components and Their Impact on Sound

To choose the right mod, you need to know which part of the system does what. Here are the primary components and how changing them affects the exhaust note.

Cat-Back Exhaust Systems

Cat-back exhausts replace everything from the catalytic converter back to the exhaust tip, including the mid-pipe and muffler. This is the most popular single upgrade because it offers a noticeable improvement in sound and a small power gain (typically 5–10 hp) without requiring major mechanical skills. Cat-back systems vary widely in tone: Borla’s “S-Type” offers a deep, aggressive growl with minimal drone, while the Invidia N1 produces a louder, more race-inspired note with pronounced pops on deceleration. GReddy’s Supreme SP is quieter at cruising speeds but opens up under throttle, ideal for daily drivers who want a refined but sporty sound. When selecting a cat-back, pay attention to pipe diameter (usually 2.5 inches is best for N/A builds) and tip size, which affects the overall look and sound character.

Axle-Back Exhausts

An axle-back system replaces only the muffler and tailpipe section, leaving the rest of the exhaust intact. It is the easiest and most cost-effective way to change the sound. Because the catalytic converter and resonator stay in place, the volume increase is moderate, but the tone shifts noticeably. Axle-backs are particularly good for owners who want a louder exhaust without committing to a full cat-back. Popular options include the Perrin 2.5” resonated axle-back (deep tone, minimal drone) and the Nameless Performance axle-back, which offers multiple muffler choices (5-inch, 4-inch, or straight pipe). The smaller the muffler, the louder and more raspy the sound. Installation typically takes under an hour with basic hand tools.

Headers: Unequal vs Equal Length

Headers are the most transformative exhaust component for the BRZ/86. The FA20 is a boxer engine, and the stock exhaust manifold is designed for emissions and torque. Aftermarket headers come in two flavors: unequal length (UEL) and equal length (EL). UEL headers mimic the sound of Subaru’s turbocharged WRX and STI models, producing that iconic rumbling, off-beat burble. This is achieved by maintaining the uneven firing pulses inherent in the boxer layout. The Tomei UEL header and the JDL UEL are top choices for that classic Subaru sound. However, UEL headers can cause issues with exhaust scavenging at higher RPMs, slightly reducing peak power (2–5 hp) compared to equal-length designs. Equal length headers, like those from Ace or JDL EL, provide a smoother, higher-pitched, almost Honda-like scream. They improve top-end power and spool for supercharged setups but lose the distinct boxer rumble. The choice between UEL and EL comes down to personal preference: rumble vs performance.

Downpipes and Front Pipes

The downpipe connects the header to the rest of the exhaust, and the front pipe links the downpipe to the cat-back. Replacing the stock front pipe with a high-flow or catless version can significantly increase volume and change the tone. A catless front pipe will make the exhaust much louder, produce a raw, metallic rasp, and may cause a check engine light without a tune. If you want a loud, aggressive setup, a front pipe upgrade is a common addition alongside a cat-back. However, be aware of local emissions laws, as removing catalytic converters is illegal for street use in many regions.

Muffler and Resonator Deletes

For the budget-conscious, muffler deletes (removing the stock muffler and replacing it with a straight pipe) are a popular DIY mod. This is often done by having an exhaust shop weld in a straight section, or by purchasing bolt-on delete kits. The result is a massive increase in volume, often accompanied by drone and rasp. Similarly, resonator deletes (removing the mid-pipe resonator) can sharpen the sound but may introduce interior resonance. These modifications are best reserved for track-only cars or those who prioritize sound over comfort. Adding a resonated mid-pipe can help tame rasp and drone if you go this route.

Choosing Your Sound Profile

“Best” is subjective. Your ideal exhaust note depends on how you use the car and what you want to feel. Here are the three main sound profiles and the mods that achieve them.

Deep and Rumbling

This profile is the signature Subaru boxer rumble: low-frequency, throaty, with a gravelly idle and a burble under deceleration. To achieve this, combine a UEL header (Tomei, JDL) with a medium-restriction cat-back like the Invidia Q300 or Borla S-Type. Avoid overly aggressive front pipes or muffler deletes, as they can introduce unwanted rasp. A resonated mid-pipe helps keep the tone deep.

Screaming and High-Pitched (Racing Tone)

If you want a sound that cuts through the air and screams to redline, go with an equal-length header (Ace, JDL EL) paired with a free-flowing cat-back like the Invidia N1 or an open straight pipe. This combination emphasizes high-frequency harmonics and produces a tone reminiscent of a tuned Honda or Porsche flat-six. It can be extremely loud, so consider adding a resonator if used on the street.

Refined and OEM-Plus

For those who want a sportier sound without drawing attention from law enforcement, focus on a high-quality cat-back with a large muffler and a Helmholtz resonator to cancel drone. The Borla S-Type and the GReddy Supreme SP excel here. Adding an overpipe with a resonator can further smooth out the note. This setup is perfect for daily drivers who still want to enjoy a crisp exhaust on back roads.

Dealing with Drone and Resonance

Drone is the low-frequency booming that occurs at a specific RPM range (usually 2,500–3,500 RPM) under cruising conditions. It can make long drives unbearable. A well-designed resonator is the best defense. Many quality cat-backs include a Helmholtz or J-pipe resonator to cancel drone frequencies. Aftermarket resonators (like Vibrant or MagnaFlow) can be added to an existing system. If you do a muffler delete, expect heavy drone. For a balanced daily driver, always choose resonated components. Also consider sound-deadening material in the trunk and rear seat area if drone is still an issue.

Installation and Tuning

Professional vs DIY

Axle-back and cat-back installations are straightforward for anyone with basic tools, ramps, and some patience. The bolts on the BRZ/86 can be stubborn due to heat and rust; use penetrating oil and have a breaker bar ready. Headers are more involved, requiring careful manipulation to clear the oil pan and often needing to lift the engine slightly. If you are not comfortable working on exhausts, a shop can install a cat-back for around $100–$150 and headers for $200–$400. Getting a professional to ensure no exhaust leaks is worth the peace of mind.

ECU Tuning After Exhaust Mods

Changing the exhaust does not require a tune on a normally aspirated BRZ/86, but it is highly recommended if you modify the header or downpipe. The FA20 runs very lean from the factory, and a tune can optimize fuel and ignition timing for the new exhaust flow, often gaining 10–15 hp and smoothing out the powerband. Platforms like OpenFlash Tablet or EcuTek provide reliable tuning solutions. Additionally, a tune can disable the check engine light that may appear with catless front pipes. If you plan to combine multiple mods (header, cat-back, intake), a custom tune is the best way to unlock the full potential.

Brand Recommendations

  • Borla: Renowned for quality, deep tone, and minimal drone. The Borla S-Type cat-back is a benchmark for the BRZ/86 community. Visit Borla
  • Invidia: Offers a range from the quieter Q300 (street) to the loud N1 (race). Great build quality and aggressive sound. Visit Invidia
  • GReddy: Known for refined, JDM-tuned exhausts. The Supreme SP and RS Race are popular for their balance of volume and tone. Visit GReddy
  • Tomei: The go-to for unequal-length headers. Their UEL header is crafted for the boxer rumble with excellent fitment. Visit Tomei
  • JDL Auto Design: Custom header builder offering both UEL and EL options, plus turbo manifolds. Highly regarded for quality and performance.
  • Ace: Top-tier equal-length headers that maximize power. Expensive but best for performance-oriented builds.

Exhaust modifications may affect your vehicle’s compliance with local noise ordinances and emissions laws. Many muffler deletes and catless setups will exceed legal decibel limits in most areas (typically 90–95 dB at idle). Removing catalytic converters is illegal for on-road use under the Clean Air Act in the US and similar regulations worldwide. Always check your local laws before purchasing. If you need to pass an emissions test, keep at least one high-flow catalytic converter and a tune that doesn’t disable O2 monitors. Many aftermarket components are CARB-exempt (like Borla’s “CARB compliant” systems), but these are rare for the BRZ/86. Consider keeping your stock parts to swap back for inspection.

Final Thoughts

The Subaru BRZ and Toyota 86 are driver’s cars that respond beautifully to exhaust work. Whether you chase the deep rumble of a UEL header or the screaming top-end of an equal-length system, the aftermarket offers endless possibilities. Start with a quality cat-back or axle-back to taste the sound, then layer in headers, front pipes, and tuning as your goals evolve. Always prioritize drone control and legal compliance if you drive daily. With the right combination, you can create an exhaust note that turns every drive into an event, without sacrificing the practicality that makes these cars so beloved.