Searching for the best cat back exhaust for Audi A4 in 2026? The right upgrade can boost performance, sound, and style, but options vary widely. The BORLA 140100 stands out as the overall best thanks to its balance of durability and aggressive tone. The MagnaFlow Touring Series offers a quieter, more refined sound for daily drivers, while the APR CBK0004 is tailored for those seeking a high-performance, race-inspired sound. Each option comes with tradeoffs—such as cost, sound level, or installation complexity—that impact suitability for different drivers. Keep reading for a detailed comparison to help you choose the perfect fit for your Audi A4.
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Key Takeaways
- The top picks offer a balance of sound, performance, and build quality, with BORLA leading for overall value.
- Sound levels vary significantly; louder options appeal to enthusiasts, while quieter systems suit daily drivers.
- Material quality, especially stainless steel, impacts durability and longevity over time.
- Installation complexity can differ; some systems require professional fitting, adding to overall costs.
- Price ranges from budget-friendly to premium, with higher cost generally correlating with better materials and sound quality.
| BORLA 140100 Cat-Back Performance Exhaust System for 2002-2008 Audi A4 B6 Quattro / A4 B7 Avant 1.8T/2.0T |  | Best Overall for Classic Audi A4 Owners | Fitment: 2002-2008 Audi A4 B6 Quattro / A4 B7 Avant | Engine Compatibility: 1.8T / 2.0T | Transmission: Automatic / Manual | VIEW ON AMAZON | See Our Full Breakdown |
| BORLA 140315 Cat-Back Performance Exhaust System for 2009-2016 Audi B8/B8.5 A4 2.0L Turbo 4-Cylinder |  | Best for Modern B8/B8.5 Audi A4 Enthusiasts | Fitment: 2009-2016 Audi B8/B8.5 A4 | Engine Compatibility: 2.0L Turbo | Transmission: Automatic / Manual | VIEW ON AMAZON | See Our Full Breakdown |
| MagnaFlow Performance Cat-Back Exhaust System Kit 15326 – Touring Series |  | Best for Signature MagnaFlow Sound and Power Gains | Fitment: 2005-2008 Audi A4 Quattro 3.2L | Exit Configuration: Dual Split Rear Exit | Material: Stainless Steel | VIEW ON AMAZON | See Our Full Breakdown |
| MagnaFlow 15519 Cat-Back Exhaust System for Audi A4 Quattro |  | Best for Aggressive Sound with OEM Fitment | Fitment: 2009-2016 Audi A4 Quattro | Pipe Diameter: 3 in. | Tip Diameter: 3.5 in. | VIEW ON AMAZON | See Our Full Breakdown |
| BORLA 140682 Cat-Back Performance Exhaust System for 2014-2020 Audi Quattro 4-Cyl, S-Type Sound, Dual Split Rear Exit, 3.5″ Round Polished T-304 Stainless Steel Tips |  | Best for Modern S-Type Sound and Premium Fit | Fitment: 2014-2020 Audi Quattro 4 Cyl. | Material: T-304 Stainless Steel | Tip Size: 3.5 inches round, polished | VIEW ON AMAZON | See Our Full Breakdown |
| APR CBK0004 Catback Exhaust System for Audi S3 Sportback 8V |  | Best Premium Quality and OEM Compatibility | Brand: APR | Part Number: CBK0004 | Material: T304 Stainless Steel | VIEW ON AMAZON | See Our Full Breakdown |
| cat back exhaust for audi a4 | Fitment | Material | Installation | Construction |
|---|---|---|---|---|
| BORLA 140100 Cat-Back Performa | 2002-2008 Audi A4 B6 Quattro / A4 B7 Avant | T-304 Stainless Steel | Bolt-On | All Welded |
| BORLA 140315 Cat-Back Performa | 2009-2016 Audi B8/B8.5 A4 | T-304 Stainless Steel | Bolt-On | All Welded |
| MagnaFlow Performance Cat-Back | 2005-2008 Audi A4 Quattro 3.2L | Stainless Steel | DIY, Bolt-On | CNC Robotic Manufacturing |
| MagnaFlow 15519 Cat-Back Exhau | 2009-2016 Audi A4 Quattro | Stainless Steel | DIY, bolt-on | — |
| BORLA 140682 Cat-Back Performa | 2014-2020 Audi Quattro 4 Cyl. | T-304 Stainless Steel | Bolt-on | All welded |
| APR CBK0004 Catback Exhaust Sy | Direct bolt-on | T304 Stainless Steel | — | — |
More Details on Our Top Picks
BORLA 140100 Cat-Back Performance Exhaust System for 2002-2008 Audi A4 B6 Quattro / A4 B7 Avant 1.8T/2.0T
This BORLA system stands out for its durable construction and authentic sound, making it a top choice for enthusiasts who want a proven, high-quality upgrade. Compared with MagnaFlow’s Touring Series, it offers a more aggressive, sporty tone that appeals to drivers seeking a more pronounced exhaust note. Its all-welded T-304 stainless steel ensures longevity, but the model’s limited compatibility—applying only to certain years and models—means it isn’t suitable for newer A4s. The bolt-on design simplifies installation without welding, yet the premium price tag might deter budget-conscious buyers. This pick makes the most sense for owners of 2002-2008 Audi A4 models who prioritize sound quality, durability, and American-made craftsmanship over cost.
Pros:- Made from high-quality T-304 stainless steel for corrosion resistance
- All-welded construction enhances durability and longevity
- Bolt-on installation simplifies setup without welding
- Delivers the signature BORLA performance sound
Cons:- Limited to specific years and models, reducing versatility
- Higher price point compared to some aftermarket options
Best for: Owners of 2002-2008 Audi A4 B6 Quattro or B7 Avant models seeking a durable, well-crafted exhaust system with a classic BORLA sound.
Not ideal for: Owners of newer Audi A4 models or those on a tight budget, as this system is model-specific and relatively expensive.
- Fitment:2002-2008 Audi A4 B6 Quattro / A4 B7 Avant
- Engine Compatibility:1.8T / 2.0T
- Transmission:Automatic / Manual
- Drivetrain:All Wheel Drive, 4 Door
- Material:T-304 Stainless Steel
- Installation:Bolt-On
- Construction:All Welded
- Country of Origin:USA
Our verdict“This system is ideal for dedicated Audi A4 owners of older models who want a durable, American-made exhaust with a rich, classic sound.”
BORLA 140315 Cat-Back Performance Exhaust System for 2009-2016 Audi B8/B8.5 A4 2.0L Turbo 4-Cylinder
This BORLA system excels for owners of the 2009-2016 B8/B8.5 Audi A4, offering a reliable, all-welded construction that produces the classic BORLA sound. Compared with the older 140100 model, it benefits from updated design features tailored to newer chassis and engine configurations, ensuring a perfect fit. Its T-304 stainless steel build guarantees corrosion resistance, but installation may require some mechanical skill, especially for those unfamiliar with exhaust work. The sound is distinctly BORLA, which appeals to drivers seeking a refined yet sporty tone. This option makes the most sense for owners of 2009-2016 Audi B8/B8.5 A4s who want a durable, American-made upgrade with a signature sound, though it’s less suitable for older models or those seeking a more aggressive tone.
Pros:- Constructed from durable T-304 stainless steel
- All-welded design for longevity
- Bolt-on installation with no welding needed
- Produces the iconic BORLA sound with a refined tone
Cons:- Limited fitment to specific years and models
- Installation may be challenging for DIY beginners
Best for: Owners of 2009-2016 Audi B8/B8.5 A4 models looking for a modern, well-made exhaust with a classic BORLA tone.
Not ideal for: Owners of older A4s or those preferring a more aggressive or louder exhaust note, as this system’s tone leans toward refined performance.
- Fitment:2009-2016 Audi B8/B8.5 A4
- Engine Compatibility:2.0L Turbo
- Transmission:Automatic / Manual
- Drivetrain:FWD/AWD
- Material:T-304 Stainless Steel
- Construction:All Welded
- Installation:Bolt-On
- Country of Origin:USA
Our verdict“This system is best suited for modern B8/B8.5 Audi A4 owners who want a durable, USA-made exhaust with a reliable, classic BORLA sound.”
MagnaFlow Performance Cat-Back Exhaust System Kit 15326 – Touring Series
The MagnaFlow 15326 Touring Series stands out for its deep, resonant sound and performance gains tailored for the 2005-2008 Audi A4 Quattro 3.2L. Unlike the BORLA options, which emphasize a sporty tone, MagnaFlow delivers a more throaty, muscle-car vibe appreciated by drivers seeking an aggressive yet refined exhaust note. Its stainless steel construction and CNC robotic manufacturing ensure high durability, with a direct-fit design that simplifies DIY installation. However, this model’s narrow fitment limits its compatibility to only 2005-2008 3.2L Quattro models, which could be a drawback for owners of other engines or newer models. If sound and performance are your priorities, this system offers a compelling upgrade, though it’s less suitable for those with different A4 variants.
Pros:- Rich, resonant MagnaFlow signature sound
- Dyno-proven performance improvements
- Robust stainless steel construction
- Easy bolt-on installation for DIYers
Cons:- Limited compatibility to specific model years and engine types
- Sound may be too aggressive for some drivers or local noise regulations
Best for: Owners of 2005-2008 Audi A4 Quattro 3.2L models seeking a deep, resonant exhaust note with improved flow and power.
Not ideal for: Drivers of newer or different engine setups, as this system is designed specifically for the 3.2L Quattro models and may not fit other variants.
- Fitment:2005-2008 Audi A4 Quattro 3.2L
- Exit Configuration:Dual Split Rear Exit
- Material:Stainless Steel
- Construction:CNC Robotic Manufacturing
- Warranty:Limited Lifetime
- Installation:DIY, Bolt-On
Our verdict“Ideal for owners of older 3.2L Quattro A4s who want a deep, powerful exhaust tone combined with performance gains.”
MagnaFlow 15519 Cat-Back Exhaust System for Audi A4 Quattro
The MagnaFlow 15519 Sport Series offers a bold, aggressive sound for the 2009-2016 Audi A4 Quattro, with its 3-inch mandrel-bent piping and dual straight-through mufflers. Compared to the MagnaFlow Touring Series, this model emphasizes a more pronounced exhaust note, which may appeal to drivers wanting a louder, more aggressive presence. Its stainless steel build ensures durability, and the OEM-like fitment means straightforward installation for DIY enthusiasts. However, the aggressive tone might be excessive for those living in noise-sensitive areas or seeking a more subdued sound. This system is best for owners who want a significant performance boost paired with a loud, aggressive exhaust tone but may not be ideal for daily commuters or those with strict noise regulations.
Pros:- Enhanced exhaust flow with 3-inch mandrel-bent piping
- Aggressive exterior and moderate interior sound
- Durable stainless steel construction
- OEM-like fitment with included hardware
Cons:- Very loud, potentially violating noise regulations
- Limited to specific model years and configurations
Best for: Owners of 2009-2016 Audi A4 Quattro models aiming for a louder, more aggressive exhaust with performance benefits.
Not ideal for: Those seeking a quieter or more refined exhaust tone, or owners of models outside the specified years and engine types.
- Fitment:2009-2016 Audi A4 Quattro
- Pipe Diameter:3 in.
- Tip Diameter:3.5 in.
- Exit Style:Dual straight driver side rear exit
- Material:Stainless Steel
- Sound Level:Aggressive exterior / Moderate interior
- Warranty:Limited lifetime
- Installation:DIY, bolt-on
Our verdict“Best suited for performance-minded owners of 2009-2016 A4 Quattro who want a loud, aggressive exhaust upgrade.”
BORLA 140682 Cat-Back Performance Exhaust System for 2014-2020 Audi Quattro 4-Cyl, S-Type Sound, Dual Split Rear Exit, 3.5″ Round Polished T-304 Stainless Steel Tips
This BORLA 140682 is tailored for the 2014-2020 Audi Quattro 4-cylinder, offering a refined, no-drone S-Type sound that appeals to drivers who want performance without sacrificing comfort. Its T-304 stainless steel build ensures long-term durability, and the polished 3.5-inch tips add a premium aesthetic. Compared to the older 140100 model, this system benefits from contemporary design improvements and a sleek finish, though it comes with a higher price tag. The bolt-on installation simplifies setup, but the premium cost might be a deterrent for budget-conscious buyers. This system makes the most sense for modern Audi owners seeking a high-quality, USA-made exhaust with a sophisticated tone, but it may be less suitable for those preferring louder or more aggressive exhaust notes.
Pros:- Premium T-304 stainless steel construction for durability
- No-drone guarantee for comfortable cruising
- S-Type sound tuning for a refined, sporty tone
- Polished 3.5-inch tips add aesthetic appeal
Cons:- Higher price compared to other brands or models
- Limited to specific model years and configurations
Best for: Owners of 2014-2020 Audi Quattro 4-cylinder models seeking a high-quality, refined exhaust with a no-drone guarantee.
Not ideal for: Drivers wanting a loud, aggressive tone or owners of older A4 models outside the specified years, as fitment and tone are tailored for newer vehicles.
- Fitment:2014-2020 Audi Quattro 4 Cyl.
- Material:T-304 Stainless Steel
- Tip Size:3.5 inches round, polished
- Exit Style:Dual split rear exit
- Sound Type:S-Type
- Installation:Bolt-on
- Construction:All welded
- Made In:USA
Our verdict“This system is best for modern Audi Quattro owners who want a durable, refined, USA-made exhaust with a sophisticated sound profile.”
APR CBK0004 Catback Exhaust System for Audi S3 Sportback 8V
The APR CBK0004 stands out for its meticulous build quality, utilizing T304 stainless steel with argon-back-purged TIG welds that promise durability and corrosion resistance. Compared to the MagnaFlow Touring Series, this system offers a more refined sound and a seamless fit for the Audi S3 Sportback, thanks to its OEM-style slip clamps and integrated electronic valve housings. It includes a Helmholtz resonator that effectively reduces drone, making it suitable for enthusiasts seeking a balance between performance and daily comfort. The system’s weight of 67 pounds might be a concern for those prioritizing ease of handling during installation. The removable tips allow for customization but could require maintenance over time. Overall, this pick makes the most sense for drivers who want a high-end, OEM-compatible upgrade with a focus on longevity and precise fit.
Pros:- Premium T304 stainless steel construction with argon-back-purged TIG welds
- Seamless OEM-style fit with direct bolt-on installation
- Includes Helmholtz resonator to minimize drone
Cons:- Heavy at 67 pounds, which may complicate installation
- Removable tips could require periodic cleaning and maintenance
Best for: Audi S3 Sportback owners who desire a premium, durable system with OEM compatibility and are willing to invest in quality.
Not ideal for: Casual users or those on a tight budget who prefer simpler, lighter systems, as this one is heavy and premium-priced.
- Brand:APR
- Part Number:CBK0004
- Material:T304 Stainless Steel
- Model:S3 Sportback Catback Kit
- Item Weight:67 lbs
- Tubing:Single 3″ to quad 2.5″ mandrel-bent
- Tips:Polished 4″ slash-cut (removable)
- Fitment:Direct bolt-on
Our verdict“This system is ideal for Audi S3 owners seeking a high-quality, OEM-compatible upgrade that emphasizes durability and refined sound, despite its weight.”
How We Picked
The products in this roundup were selected based on performance, durability, ease of installation, and value for money. Priority was given to systems that fit multiple Audi A4 model years, ensuring broad compatibility. We also considered customer reviews and expert opinions regarding sound quality and build materials. Ranking was influenced by a balance of these factors, favoring options that deliver consistent performance and quality at different price points. Our goal was to identify choices suitable for a range of drivers—from enthusiasts seeking aggressive sound to daily commuters prioritizing reliability.| cat back exhaust for audi a4 | Material | Installation | Construction |
|---|---|---|---|
| BORLA 140100 Cat-Back Performa | T-304 Stainless Steel | Bolt-On | All Welded |
| BORLA 140315 Cat-Back Performa | T-304 Stainless Steel | Bolt-On | All Welded |
| MagnaFlow Performance Cat-Back | Stainless Steel | DIY, Bolt-On | CNC Robotic Manufacturing |
| MagnaFlow 15519 Cat-Back Exhau | Stainless Steel | DIY, bolt-on | — |
| BORLA 140682 Cat-Back Performa | T-304 Stainless Steel | Bolt-on | All welded |
| APR CBK0004 Catback Exhaust Sy | T304 Stainless Steel | — | — |
Factors to Consider When Choosing Cat Back Exhaust For Audi A4
Choosing the right cat back exhaust for your Audi A4 involves more than just brand names; understanding key factors can help you avoid common pitfalls and select a system that enhances your driving experience. Consider your priorities—whether it’s sound, performance, durability, or budget—and how they align with your vehicle’s use. A well-chosen exhaust can improve throttle response and give your A4 a more aggressive tone, but a poor choice might lead to increased noise or installation issues. Here are some important considerations to keep in mind.Sound Level and Tone
Sound is often the primary reason for upgrading an exhaust. Some systems produce a deep, aggressive tone, ideal for enthusiasts who want a sporty feel. Others are designed for a quieter, more refined sound suitable for daily commuting. Be aware that louder exhausts can sometimes attract unwanted attention or violate noise regulations in certain areas. Choosing a system that matches your preferred sound profile ensures satisfaction without surprises after installation.
Material Quality and Durability
Stainless steel is the standard for durability and corrosion resistance, especially T-304 grade, which withstands harsh conditions better than cheaper alloys. A higher-quality material often justifies a higher price, offering longer lifespan and less maintenance. Cheaper options may rust or degrade faster, leading to costly replacements. For those who want a long-term upgrade, investing in a stainless steel system can save money and hassle down the line.
Performance Gains
While a cat back exhaust can improve exhaust flow and slightly boost horsepower, the real gains depend on the system’s design and how it complements your vehicle’s engine. Some systems are optimized for maximum performance, often at the expense of increased noise. If you’re aiming for measurable power improvements, look for systems with mandrel bends and free-flowing designs. For casual drivers, however, a focus on sound and aesthetics might be more appropriate than performance metrics alone.
Ease of Installation
Not all systems are plug-and-play; some require cutting, welding, or professional fitting, which can add to total costs. Carefully check the installation instructions and compatibility with your specific Audi A4 model. If you plan to install the system yourself, choose options that are designed for straightforward fitting, often with clamp-on connections and detailed guides. For those unfamiliar with automotive work, professional installation might be worth the extra expense to ensure proper fit and function.
Budget and Value
Exhaust systems range from budget-friendly to premium setups. Cheaper systems might save money upfront but often compromise on sound quality, durability, or fit. Conversely, premium options typically feature better materials and more aggressive tuning, but at a higher cost. Assess your priorities—if you want a durable, performance-oriented system, investing more can pay off. Budget-conscious buyers should focus on reputable brands that balance cost and quality effectively.
Frequently Asked Questions
Will upgrading to a cat back exhaust improve my Audi A4’s horsepower?
While a cat back exhaust can enhance exhaust flow, the noticeable horsepower gains are usually modest unless paired with other modifications. Most systems improve throttle response and sound more than adding significant power. If you’re seeking substantial performance improvements, consider combining the exhaust upgrade with engine tuning or intake modifications. For everyday driving, the primary benefits are sound and aesthetics, with only slight performance boosts.
Is a louder exhaust system legal in all areas?
Not necessarily. Many regions have noise regulations that restrict certain loud exhaust systems, especially those with aggressive tones. Before installing a louder system, check local laws to ensure compliance. Some systems offer adjustable sound levels or quieter modes, which can help avoid legal issues. Remember, exceeding noise limits can lead to fines or the need to revert to stock components, so choose accordingly based on your local regulations.
Can I install a cat back exhaust myself, or do I need a professional?
Installation difficulty varies depending on the system and your mechanical skills. Many clamp-on designs are straightforward and suitable for DIY installation with basic tools, but some may require cutting or welding, which is best handled by professionals. If you lack experience or tools, hiring a mechanic ensures proper fit, seal, and performance. Consider your comfort level and the complexity of the system before deciding whether to install it yourself or seek expert help.
How does the material of the exhaust affect its lifespan?
Material quality is critical for durability. Stainless steel, especially T-304 grade, resists rust and corrosion far better than aluminized or mild steel systems. Cheaper materials tend to degrade faster, especially in areas with harsh weather or road salt exposure. Investing in a higher-grade stainless steel system typically results in a longer-lasting exhaust that maintains its appearance and performance over time, making it a smarter long-term choice.
Is it worth paying more for a premium exhaust system?
Premium systems often provide better materials, enhanced sound, and improved performance characteristics, which can justify the higher cost for enthusiasts or daily drivers seeking reliability. They tend to have longer lifespans and require less maintenance. However, for casual drivers or those on a tight budget, a mid-range system from a reputable brand may deliver most of the desired benefits without the premium price. Carefully consider your priorities and how much you’re willing to invest for the features that matter most to you.
Conclusion
If you’re after the best overall balance of sound, durability, and value, the BORLA 140100 makes a compelling choice. For beginners or budget-conscious drivers, a simpler, more affordable system with decent sound quality can suffice. Enthusiasts seeking a premium, race-inspired sound might prefer the APR CBK0004 despite its higher cost. Those looking for a quieter, refined experience should consider MagnaFlow’s Touring Series. Ultimately, your choice depends on your priorities—performance, sound level, budget, or ease of installation—and this guide aims to help you find the perfect match for your Audi A4.
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