8 Performance Benefits of Upgrading Your BMW M4 Exhaust
Milltek Exhaust is a well-known brand that specialises in crafting top-notch exhaust systems for various vehicles, including sports cars, luxury models, and even race cars. They're highly regarded for their expertise in creating custom exhaust solutions that cater to the needs of car enthusiasts and professional racing teams worldwide.
Milltek Exhausts
The BMW M4 is an engineering masterpiece, combining aggressive styling with track-ready performance. However, even this high-performance machine has room for improvement—especially when it comes to the exhaust system. Upgrading your BMW M4 exhaust can significantly enhance your car’s power, sound, and efficiency, giving you a more thrilling driving experience.
In this guide, we’ll dive into the eight performance benefits of upgrading your BMW M4 exhaust, explaining why it’s one of the best modifications you can make.
1. Increased Horsepower and Torque
One of the biggest advantages of upgrading your M4’s exhaust system is the increase in horsepower and torque. The stock exhaust, while well-designed, is built to meet emissions and noise regulations, which can restrict performance.
Aftermarket exhaust systems feature:
- Larger diameter piping for better airflow
- Mandrel bends to reduce restrictions
- High-flow catalytic converters or catless options
These improvements reduce backpressure, allowing your BMW M4’s S58 engine to breathe better and produce more power. On average, a high-quality exhaust upgrade can add 10-30 horsepower, depending on the setup.
2. Improved Throttle Response
A restrictive exhaust system can cause delays in how quickly your engine responds to throttle inputs. Upgrading to a performance exhaust system improves exhaust scavenging, meaning the engine expels gases more efficiently.
With improved airflow, your M4’s twin-turbo inline-six can reach peak performance faster, translating to sharper acceleration and a more connected driving experience.
3. Enhanced Exhaust Sound
One of the most noticeable upgrades from an aftermarket exhaust is the aggressive, sporty exhaust note. The stock M4 exhaust is somewhat muted to comply with regulations, but an aftermarket system unlocks the true sound of your car.
Depending on your preference, you can choose:
- Cat-back exhausts for a deeper, more refined tone
- Axle-back systems for mild sound improvements
- Full exhaust systems with downpipes for an all-out roar
4. Weight Reduction for Better Handling
Many aftermarket exhaust systems are made from lightweight materials like titanium or stainless steel, significantly reducing weight compared to the bulky stock exhaust. A titanium exhaust, for example, can cut up to 20-30 lbs, improving:
- Power-to-weight ratio for better acceleration
- Handling and cornering response
- Fuel efficiency (slightly) due to less weight
By shedding unnecessary weight, you make your M4 even more agile on the road and track.
5. Increased Fuel Efficiency
Although most people upgrade their BMW M4 exhaust for performance and sound, fuel efficiency can also improve. A more efficient exhaust system reduces the engine’s workload, meaning it burns fuel more effectively.
With:
- Better airflow
- Reduced backpressure
- Optimized fuel-air mixture
You may see a slight improvement in miles per gallon (MPG), especially during highway driving. While it won’t drastically change fuel economy, every little bit helps.
6. Lower Exhaust Temperatures
A performance exhaust helps lower engine bay and exhaust system temperatures by allowing hot gases to exit the system more efficiently.
Benefits of lower exhaust temperatures include:
- Less heat soak (helps maintain consistent power)
- Reduced risk of engine knock
- Longer lifespan for engine components
High-performance materials like ceramic-coated headers or wrapped downpipes can further reduce heat buildup, improving overall reliability.
7. Customization Options
One of the best things about upgrading your BMW M4 exhaust is the ability to customize it to fit your driving style and goals. Whether you want a valved exhaust system for adjustable sound levels or a quad-tip design for a more aggressive look, there are endless options.
Popular exhaust styles include:
- Single mid-pipe setups for improved flow and sound
- X-pipes or H-pipes to fine-tune exhaust pulses
- Carbon fiber or titanium tips for a premium aesthetic
Customization allows you to tailor your M4’s exhaust note and performance to match your personal preference.
8. Increased Resale Value and Appeal
A well-chosen aftermarket exhaust can increase the resale value of your M4, as many enthusiasts prefer a car with performance upgrades. If you choose a high-quality, well-known brand, potential buyers may be willing to pay more for a car that already has premium modifications.
To maintain resale value, it’s important to:
- Choose a reputable brand like Akrapovič, Eisenmann, or Milltek
- Keep stock components in case a buyer wants to revert to OEM
- Ensure the exhaust is street-legal if selling in a regulated area
With the right exhaust setup, your BMW M4 will not only perform better but also attract more interest when it’s time to sell.
Final Thoughts
Upgrading your BMW M4 exhaust is one of the most effective ways to enhance performance, sound, and overall driving enjoyment. From increased horsepower to a more aggressive exhaust note, the benefits are clear.
If you’re looking for an exhaust upgrade for another BMW model, such as the BMW 120i exhaust, many of the same principles apply. Improved airflow, better sound, and weight reduction can benefit any BMW performance car.
Whether you’re a weekend track warrior or a daily driver looking for more excitement, an upgraded exhaust system is a must-have modification for any M4 enthusiast.
