The Ultimate Guide to an M5 G90 Full Exhaust System Upgrade

The BMW M5 has always been a paradox on wheels—a sophisticated executive sedan that hides a savage, high-revving heart beneath its elegant shell. With the new G90 generation, BMW has taken this concept to a stratospheric level. But for true enthusiasts, the symphony composed by BMW's engineers, while impressive, is often just the opening act. The real masterpiece begins when you unlock the car's full aural potential.

Enter the full exhaust system upgrade. This isn't just about making noise; it's about elevating performance, enhancing character, and tailoring the car's voice to your soul. Today, we're diving deep into the world of full exhaust systems for the G90 M5, covering everything from the essential downpipe to the roaring catback.

Why Go Full Exhaust? More Than Just a Loud Pedal

While a simple catback modification can change the sound, a full exhaust system (header-to-tailpipes) is a holistic transformation. Here’s why it’s the gold standard for serious modifiers:

1.Unrestricted Flow & Power Gains: The primary bottleneck in any factory exhaust is the downpipe (or header). It contains catalytic converters designed to clean emissions but also restrict exhaust gas flow. By replacing the stock headers with high-flow catted or catless versions, you significantly reduce backpressure. This allows the twin-turbocharged V8 to exhale more freely, often resulting in substantial gains in horsepower and torque, especially when paired with a dedicated ECU tune.

2.A Deeper, More Authentic Sound: The factory system is muffled and filtered to meet strict sound regulations. A full system replaces the restrictive mid-pipes and mufflers with straight-through designs. This reveals the true, raw, and unfiltered soundtrack of the 4.4-liter S68 engine—a deep, guttural roar at low RPMs that transforms into a high-octane scream at the redline.

3.Weight Reduction: Many aftermarket systems are crafted from premium, lightweight materials like T304 or T409 stainless steel, or even titanium for the ultimate weight-saving option. Swapping out the heavy OEM setup can shed dozens of pounds from the car, improving agility and handling.

3. Aesthetic Appeal: Let’s not forget the visual upgrade. A full system typically ends with larger, beautifully finished tips—be they carbon fiber, titanium blue, or polished stainless steel—that fill out the rear diffuser perfectly and signal the serious intent of your machine.

The Anatomy of a Full Exhaust System: From Downpipes Back

A "full" or "complete" system is a journey from the engine block to the rear bumper.

Downpipes: This is where the magic starts. Replacing these is the single most impactful mod for both power and sound. It unleashes the most heat and energy from the turbos. Options range from high-flow catted (a great balance of performance, smell, and some environmental conscience) to catless (maximum flow and aggression, but not street-legal in many areas and will produce a stronger odor).

Mid-Pipe (X-Pipe or H-Pipe): This section connects the downpipes to the rear muffler. An X-pipe is the most common upgrade, helping to merge the exhaust pulses from both banks of the V8 to create a smoother, higher-pitched, and more exotic Ferrari-like sound. An H-pipe tends to produce a deeper, old-school muscle car rumble.

Catback / Muffler Delete: The final piece of the puzzle. This section houses the mufflers and determines the final volume and tone. A valved system is highly recommended for the G90 M5, allowing you to switch between a civilized "quiet" mode for early morning departures and an earth-shattering "loud" mode for track days or open roads.

The Ultimate Customization: Building Your M5's Signature Voice

This is where the aftermarket truly shines. A full exhaust upgrade is not a one-sound-fits-all proposition. It’s the ultimate form of acoustic customization.

Material Choice: Do you go with the classic resonance of stainless steel or the extreme lightweight and unique percussive sound of titanium?

Tip Finish: Choose from polished silver, black ceramic coating, glossy carbon fiber, or the gorgeous titanium blue burnished finish to match your car's aesthetic.

Valve Control: Remote for manual control over the soundscape at your fingertips.

Sound Level: By mixing and matching components (e.g., high-flow catted downpipes with a valved axle-back), you can fine-tune the volume to be exactly what you want—from assertive and mature to all-out race car.

The Final Verdict

Investing in a full exhaust system for your BMW G90 M5 is one of the most rewarding modifications you can make. It’s a transformation that engages all the senses: the feel of the increased power, the sight of gorgeous tips, and the sound of a unleashed V8 symphony.

It’s about turning the already phenomenal G90 from a machine of compromise into a machine of pure, unadulterated passion. It’s not just an upgrade; it’s the completion of the M5's true identity.

Ready to define your M5's roar? Contact Jagrow Performance and to get the perfect sugguestions.