Mercedes-Benz CLS63 AMG Exhaust Upgrade Review

Mercedes-Benz CLS63 AMG Custom Exhaust: Why Upgrade?

The Mercedes-Benz CLS63 AMG is a performance sedan known for its powerful exhaust note. However, many owners seek a deeper, more aggressive sound than the stock system provides. This review details a full exhaust system upgrade, from the mid-pipe to the muffler, designed to transform the CLS63 AMG's auditory presence.

This Article Covers:
— Pre-installation vehicle inspection
— Mid-pipe replacement process
— End muffler installation
— Exhaust pressure optimization
— Post-installation sound verification

Analyzing the Stock CLS63 AMG Exhaust System

Upon arrival, the vehicle's stock exhaust system was inspected. While visually sound, it lacked the desired sonic character. Stock mufflers are designed to meet strict noise regulations, often resulting in a muted sound profile. The owner's request was for a "tiger-like roar," signifying a deep, resonant tone with a clear, powerful note during acceleration.

Beyond sound, optimizing the exhaust system is crucial for performance. A well-designed system allows exhaust gases to exit more efficiently, reducing backpressure. This improved "breathing" for the engine can lead to noticeable performance gains.

Mid-Pipe Replacement: The Heart of the Upgrade

The exhaust system comprises several key components: the downpipe (closest to the engine), the mid-pipe (including the catalytic converter and resonator), and the end mufflers. The mid-pipe plays a critical role in both sound reduction and flow dynamics.

Stock mid-pipes often feature complex internal baffling to dampen sound. Replacing this with a performance-oriented unit involves redesigning the internal chambers for optimal flow and acoustics. In this CLS63 AMG upgrade, a custom mid-pipe with precisely calculated diameter, length, and internal routing was installed. The pipe diameter was increased to 3.5 inches (approximately 89mm) to minimize flow resistance.

Durability and heat management are paramount. To withstand the high temperatures of exhaust gases, 304 stainless steel was used, ensuring stability even above 800°C and preventing deformation common with standard steel.

End Muffler Installation: Fine-Tuning the Sound

The final stage involves installing the end mufflers, which are responsible for the exhaust's final sound signature. Key considerations for muffler selection include acoustic characteristics (depth and tone), backpressure effects on performance, and aesthetic integration with the vehicle.

The CLS63 AMG features a dual exhaust outlet, requiring custom mufflers for each side to ensure proper balance and sound delivery. Precise alignment of the exhaust tips with the vehicle's bodywork, adjusted to the millimeter, is essential to prevent unwanted resonance or drone. Vibration dampers were also strategically placed to further mitigate noise and vibration.

Exhaust Backpressure Optimization: Balancing Performance and Sound

Achieving an aggressive exhaust note is only part of a proper upgrade. Maintaining optimal backpressure is crucial for engine performance. Excessive reduction in backpressure without proper tuning can negatively impact low-end torque and overall drivability. This upgrade focused on creating a system that delivers a powerful sound while complementing the CLS63 AMG's inherent performance characteristics.

Installation Process:
1. Removal of the stock exhaust system components.
2. Precise fitting and welding of the custom mid-pipe.
3. Mounting and alignment of the new end mufflers.
4. Final inspection and sound testing.