If you own a Subaru BRZ or Toyota 86, you already appreciate the unique character of the boxer engine that powers these iconic sports cars. The naturally aspirated FA20 engine delivers respectable performance, but many enthusiasts find the factory exhaust note somewhat subdued and lacking the auditory excitement that complements spirited driving. Upgrading your exhaust system is one of the most effective ways to transform the sound of the car, adding personality, excitement, and a deeper visceral connection to the driving experience. Whether you prefer a subtle enhancement in volume or a full-throated, track-ready roar, this comprehensive guide details the best exhaust sound modifications available for the Subaru BRZ and Toyota 86, along with the technical nuances that influence tone, volume, and overall character.

Understanding the FA20 Engine and Exhaust Acoustics

The Subaru FA20 engine is a 2.0-liter four-cylinder horizontally opposed (boxer) engine, renowned for its low center of gravity and balanced design. Its unique firing order and symmetrical cylinder layout create exhaust pulse timing that differs significantly from inline or V-configurations. This distinct exhaust pulse pattern, when paired with the right exhaust components, produces a sound that stands apart from typical four-cylinder engines.

However, the stock exhaust system on the BRZ/86 is engineered primarily for emissions compliance, noise regulation, and interior comfort. This means it often muffles the engine’s natural voice, restricting airflow and muting the exhaust note. To unlock a more engaging sound, it's important to understand how each exhaust component shapes the acoustic signature. Every part—from the headers to the tailpipe—modifies the pressure waves and harmonics, influencing tone quality, loudness, drone, and even performance.

Exhaust System Components and Their Effect on Sound

When modifying your exhaust, it’s crucial to know what each component does and how alterations affect sound and performance. Below is an overview of the primary parts of the exhaust system and their acoustic impacts.

Cat-Back Exhaust Systems

Cat-back exhaust systems replace the section of the exhaust from the catalytic converter back to the exhaust tip, including the mid-pipe and muffler. This upgrade is the most popular among BRZ/86 owners because it delivers a noticeable improvement in sound character and a modest power gain—typically between 5 and 10 horsepower—without requiring extensive mechanical knowledge.

Cat-back systems vary widely in tone and volume. For example, Borla’s S-Type cat-back offers a deep, aggressive growl with minimal drone, making it a favorite for enthusiasts who want a muscular yet refined sound. In contrast, the Invidia N1 cat-back produces a louder and more race-inspired tone, characterized by sharp pops and crackles on deceleration, perfect for track enthusiasts. Meanwhile, the GReddy Supreme SP cat-back balances a quiet cruising tone with a sporty bark under acceleration, ideal for daily drivers who want a subtle yet sporty exhaust note.

When selecting a cat-back, consider pipe diameter (most naturally aspirated BRZ/86 builds benefit from 2.5-inch piping for optimal flow without excessive drone) and tip design, which influences both sound dispersion and aesthetic appeal.

Axle-Back Exhaust Systems

Axle-back systems replace only the muffler and tailpipe section of the exhaust, leaving the catalytic converter and mid-pipe intact. This makes axle-backs the quickest, easiest, and most affordable way to alter your car’s exhaust sound. Because the catalytic converter and resonator remain, volume increases are moderate, but the tonal character can shift significantly.

Axle-back exhausts suit owners who want a slightly louder, more aggressive exhaust without the expense or complexity of a full cat-back system. Notable options include the Perrin 2.5-inch resonated axle-back, which delivers a deep, refined tone with minimal drone, and the Nameless Performance axle-back, which offers multiple muffler options ranging from 5-inch mufflers for a quieter tone to straight pipes for maximum volume and rasp. Installation is typically straightforward and can be completed with basic hand tools within an hour.

Headers: Unequal Length (UEL) vs Equal Length (EL)

Headers are arguably the most transformative exhaust component for tuning the BRZ/86’s sound. The factory exhaust manifold emphasizes emissions and torque delivery, but aftermarket headers can dramatically change sound and performance. Headers collect exhaust gases from the engine cylinders and direct them into the exhaust system, influencing pulse timing and scavenging effects.

Two primary header designs are available:

  • Unequal Length Headers (UEL): These maintain the FA20’s natural exhaust pulse timing and reproduce the classic Subaru rumble. Unequal length headers produce an off-beat burble and deep, gravelly idle reminiscent of Subaru’s turbocharged WRX and STI models. This is achieved by having pipes of different lengths, which preserves the boxer engine's characteristic uneven firing pulses. The Tomei UEL header and JDL UEL headers are widely regarded as the best options for achieving this signature rumble.
  • Equal Length Headers (EL): These feature identical-length primary pipes, which improve exhaust scavenging and create a smoother, higher-pitched scream. Equal length headers maximize exhaust flow efficiency, especially at high RPMs, and are preferred for supercharged or high-revving builds. Brands like Ace and JDL EL headers offer this design, producing a tone more akin to high-performance naturally aspirated engines such as tuned Hondas or Porsche flat-sixes, albeit at the cost of losing the distinct boxer rumble.

Choosing between UEL and EL headers depends largely on personal preference: UEL for that deep, rumbling boxer character, or EL for a sharper, race-inspired scream that prioritizes peak power.

Downpipes and Front Pipes

The downpipe connects the headers to the rest of the exhaust system, while the front pipe links the downpipe to the cat-back portion. Upgrading to high-flow or catless front pipes can dramatically increase exhaust volume and alter tonal qualities.

A catless front pipe removes the catalytic converter, resulting in a raw, metallic rasp and significantly louder exhaust. However, this often triggers a check engine light unless paired with an ECU tune. Catless pipes are favored in racing setups but are typically illegal for street use in many jurisdictions due to emissions regulations. High-flow front pipes with catalytic converters provide a compromise, increasing flow and volume while maintaining emissions compliance.

For enthusiasts seeking an aggressive, loud setup, pairing a catless or high-flow front pipe with a cat-back system is a common strategy. However, always be aware of your local laws regarding catalytic converters and emissions.

Muffler and Resonator Deletes

Muffler deletes involve removing the factory muffler and replacing it with a straight pipe, which significantly increases exhaust volume and aggressiveness. Similarly, resonator deletes remove the resonator section of the mid-pipe, sharpening the exhaust tone and increasing raspiness.

These modifications are popular with budget-conscious enthusiasts or those building dedicated track cars. However, muffler and resonator deletes typically introduce substantial drone—an unpleasant low-frequency boom—especially during highway cruising. This can make long drives fatiguing and may annoy passengers.

To mitigate drone, some opt for resonated mid-pipes or aftermarket resonators designed to cancel specific frequencies. Ultimately, muffler and resonator deletes are best suited for track use or owners prioritizing sound over comfort and legality.

Choosing Your Ideal Exhaust Sound Profile

The “best” exhaust sound is subjective and depends on your usage, preferences, and tolerance for noise and drone. Below are three common tonal profiles and the modifications that achieve them.

Deep and Rumbling Boxer Growl

This sound profile embodies the classic Subaru boxer rumble: a low-frequency, throaty growl with a gravelly idle and a pleasant burble on throttle lift and deceleration. It’s warm, inviting, and unmistakably Subaru.

To achieve this, combine a UEL header (such as the Tomei or JDL UEL) with a medium-restriction cat-back exhaust like the Invidia Q300 or Borla S-Type. Avoid excessively aggressive front pipes or muffler deletes, as these can introduce harsh raspiness that undermines the deep tone. Incorporating a resonated mid-pipe helps maintain a rich, deep sound while controlling unwanted resonance and drone.

Screaming High-Pitched Racing Tone

If you crave a loud, high-pitched scream that carries to redline, an equal length header paired with a free-flowing cat-back is your best choice. This setup emphasizes high-frequency harmonics, producing a sharp, energetic sound reminiscent of tuned Honda VTEC engines or Porsche flat-sixes on the track.

Brands like Ace and JDL EL headers combined with aggressive cat-backs such as the Invidia N1 or an open straight pipe deliver this racing-inspired sound. This profile is loud and attention-grabbing, so it may require the addition of a resonator for street use to avoid excessive drone and comply with noise regulations.

Refined and OEM-Plus Sound

For enthusiasts who want a sportier exhaust note without excessive volume or drone, a high-quality cat-back system with a large muffler and integrated resonators is ideal. This setup enhances the factory tone, adding crispness and depth while maintaining discretion.

The Borla S-Type and GReddy Supreme SP cat-backs excel in this category, offering a polished, balanced sound profile that’s suitable for daily driving and spirited backroad runs. Adding an overpipe or mid-pipe with a Helmholtz resonator further smooths out the tone and reduces cabin resonance, resulting in a comfortable yet engaging exhaust character.

Addressing Drone and Interior Resonance

One of the most common complaints among exhaust enthusiasts is drone—a persistent low-frequency boom that occurs at certain RPMs, typically between 2,500 and 3,500 RPM during steady cruising. Drone can make highway driving uncomfortable and fatiguing, diminishing the enjoyment of your exhaust upgrades.

The most effective solution to drone is a well-designed resonator. Many premium cat-back systems incorporate Helmholtz or J-pipe resonators engineered to cancel out these specific sound frequencies. If your system lacks a resonator, aftermarket options from brands like Vibrant or MagnaFlow can be added to attenuate drone.

It’s important to note that muffler and resonator deletes greatly increase the likelihood of drone. Therefore, if you prioritize a daily driver that’s enjoyable both on spirited drives and during commutes, choose resonated components. Additionally, applying sound-deadening materials in the trunk and rear passenger areas can reduce cabin resonance and improve comfort.

Installation and Tuning Considerations

Professional Installation vs DIY

Installing axle-back and cat-back exhaust systems on the BRZ/86 is generally straightforward for enthusiasts with basic hand tools, ramps or a lift, and patience. Bolts and hangers can be stubborn due to heat cycling and rust, so penetrating oil and a breaker bar are highly recommended. Installation time for a cat-back typically ranges from one to two hours.

Headers are more complex to install. They require careful maneuvering to clear the oil pan and often involve loosening or removing engine mounts to provide clearance. Additionally, proper torque sequencing and ensuring leak-free gaskets are critical. For these reasons, many opt for professional installation of headers, which typically costs between $200 and $400, while cat-back installs range from $100 to $150. Investing in professional installation ensures proper fitment, reduces the risk of leaks, and provides peace of mind.

ECU Tuning After Exhaust Modifications

While simple cat-back or axle-back upgrades on a naturally aspirated BRZ/86 usually don’t require ECU tuning, more extensive modifications—especially header or downpipe changes—benefit greatly from a proper tune. The FA20 engine runs slightly lean from the factory to meet emissions, and a tune can optimize air-fuel ratios, ignition timing, and throttle response to match the new exhaust flow characteristics.

Tuning often results in smoother power delivery, elimination of hesitations, and horsepower gains in the range of 10 to 15 hp. Additionally, if you remove catalytic converters (e.g., with a catless front pipe), a tune is essential to prevent check engine lights and maintain driveability.

Popular tuning platforms for the BRZ/86 include the OpenFlash Tablet and EcuTek. These solutions enable custom maps and allow you to disable unwanted fault codes related to emissions equipment removal. For multi-mod setups involving headers, intake, and exhaust, a custom dyno tune is the best way to fully unlock your car’s potential.

  • Borla: Known for premium build quality, deep and aggressive tone, and minimal drone. The Borla S-Type cat-back is a benchmark upgrade widely praised by the BRZ/86 community. Visit Borla
  • Invidia: Offers a spectrum of options from the quieter Q300 (ideal for street use) to the loud and aggressive N1 race exhaust. Their products are well-built and deliver a commanding sound. Visit Invidia
  • GReddy: Renowned for refined JDM-inspired exhausts. The Supreme SP and RS Race cat-backs balance volume and tone perfectly for daily drivers wanting a sportier sound. Visit GReddy
  • Tomei: The go-to brand for unequal-length headers designed to produce the classic Subaru boxer rumble. Known for excellent fitment and durable construction. Visit Tomei
  • JDL Auto Design: A custom header specialist offering both UEL and EL headers, as well as turbo manifolds. Highly regarded for quality, sound, and performance on the BRZ/86 platform.
  • Ace: Premium equal-length headers focusing on maximum power gains and smooth high-RPM sound. Ace headers are more expensive but ideal for performance-oriented builds.
  • Perrin Performance: Offers resonated axle-back systems and front pipes that strike a balance between sound quality and daily drivability. Known for solid construction and good fitment.

Before modifying your exhaust, it’s vital to understand the legal and environmental implications. Many exhaust modifications, especially muffler deletes and catless setups, exceed local noise ordinances and emissions standards. Typical noise limits hover around 90–95 decibels at idle, and many aftermarket systems surpass this, resulting in fines or failed inspections.

Removing or bypassing catalytic converters is illegal for street use under the Clean Air Act in the United States and similar environmental regulations worldwide. Such modifications can cause your vehicle to fail emissions tests and may lead to penalties.

To remain compliant, consider retaining at least one high-flow catalytic converter or using CARB-exempt systems where available. Some aftermarket manufacturers offer CARB-compliant exhausts for the BRZ/86, though options are limited. Always verify local laws and regulations before purchasing or installing exhaust components. Retaining your stock exhaust parts for inspections or resale is also a prudent practice.

Final Thoughts

The Subaru BRZ and Toyota 86 are celebrated driver’s cars that respond beautifully to thoughtful exhaust modifications. Whether you pursue the deep, characteristic rumble of an unequal-length header or the screaming top-end of an equal-length system, the aftermarket provides a wealth of options to tailor your exhaust note to your preferences.

Starting with a quality cat-back or axle-back system is an excellent way to explore new sound profiles. From there, layering in headers, front pipes, and ECU tuning can elevate performance and sonic character to new heights. Always prioritize drone control and legal compliance if you plan to drive daily, and consider professional installation and tuning for best results.

With the right combination of parts and expertise, you can craft an exhaust sound that turns every drive into an event—enhancing not only performance but also the emotional connection to your BRZ or 86.