G90 Signature Catback Exhaust System

Stainless Steel Valved Full Exhaust System – BMW G90 M5 (S68 Twin-Turbo V8-Hybrid)

Transform the performance and sound of your 2025+ BMW G90 M5 with our premium T304 stainless steel valved full exhaust system. Purpose-built for the S68 4.4L twin-turbo V8, this system is engineered to enhance exhaust flow, reduce backpressure, and deliver a deep, aggressive tone—without compromising daily drivability.

Designed using advanced techniques for a precise OEM-fit, this exhaust system integrates seamlessly with all factory mounting points and adds exhaust valve control which is missing from the OEM exhaust system. Whether cruising or pushing the limits, this system provides an immersive and exhilarating exhaust experience.

Key Highlights:

T304 Stainless Steel Construction: Built entirely from corrosion-resistant, mandrel-bent T304 stainless steel, this system offers long-term durability, heat resistance, and a consistent finish. Welded with precision using TIG methods to ensure structural integrity and leak-free performance under high-load conditions.

Remote control Exhaust Valves: Adds an electronic valve system controlled by a remote to replace the missing exhaust valves BMW did not provide with the stock exhaust. Provides a quiet, subdued tone in comfort modes and an aggressive, open-valve growl in dynamic settings—no tuning or coding required.

High-Flow X-Pipe Midsection: Centralized X-pipe balances exhaust pulses between banks, improving scavenging and enhancing the natural V8 rhythm. Reduces unwanted drone and enhances top-end acoustics under throttle.

Performance-Oriented Flow Path: Oversized and optimized 3.5” (89mm) piping diameter ensures efficient flow, minimizes turbulence, and maximizes power delivery throughout the rev range. Estimated gains of +18–22 hp and +20–25 lb-ft torque (with optional EPA catted downpipes).

Optional High-Flow Catted Downpipes: Available as an upgrade, our 400-cell GESI catalytic converters maintain emissions compliance (region-dependent) while increasing turbo efficiency and reducing spool time. CNC-machined flanges and heat shielding ensure fitment and thermal control.

Sound Engineering: Precision-tuned for a refined cold start, deep idle rumble, and aggressive throttle response. The system delivers a clean, motorsport-inspired tone without unwanted cabin drone—ideal for both spirited driving and long highway trips.

Quad 112mm Exhaust Tips (Multiple Finishes): Choose from brushed stainless, matte black  or carbon fiber quad tips to match your M5’s styling. Dual-wall design resists heat discoloration and adds a premium finish to the rear profile.

Direct Bolt-On Installation: No cutting, welding, or modification required. Includes all clamps, gaskets, valve motor brackets, valve motors with remotes and hardware. Fully reversible for lease or resale.

Specifications:

                • Material: T304 Stainless Steel

                • Tubing Diameter: 3.5” (89mm) from downpipes to rear exhaust

                • Valves: Electronic remote control plug-and-play

                • Weight Reduction: ~10–12 lbs vs. OEM system

                • Tip Diameter: 112mm (quad outlet)

                • Fitment: BMW G90 M5 (2025+) / G99 M5 Touring

Why Choose This Exhaust System?

This full stainless system offers the perfect balance of durability, sound tuning, and performance gains—without sacrificing luxury or OEM integration. Ideal for enthusiasts looking for a visceral exhaust experience with the peace of mind of factory compatibility and high-quality materials.

Unlock the full potential of your G90 M5. Let it breathe, let it roar.