SPDZ1 B46 Stainless Steel Downpipe Upgrade – BMW G20 320i xDrive (B46 Engine) 2019+ BMW 320i xDrive (G20 Chassis)

Unlock hidden power and improve turbocharger response with the SPDZ1 High-Performance Downpipe Upgrade for the BMW B46-powered G20 320i xDrive. Designed for enthusiasts seeking optimal performance and reliability, our downpipe dramatically improves exhaust flow by removing the restrictive OEM catalytic converter—maximizing efficiency and enhancing sound under boost.

Key Features:

• CNC-Crafted for Direct Fitment
  Designed using 3D scans and CAD modeling, the SPDZ1 downpipe offers true plug-and-play fitment with factory turbo and exhaust components. No cutting or welding required.
• Mandrel-Bent T304 Stainless Steel Construction
  Built from 100% mandrel-bent T304 stainless steel for unmatched durability, corrosion resistance, and heat resilience. All welds are TIG-finished by skilled fabricators to ensure long-term performance under high-load conditions.
• Optimized Internal Diameter
  Flow-optimized piping reduces backpressure and increases exhaust velocity, improving turbo spool and minimizing turbo lag. This results in noticeable horsepower and torque gains when paired with tuning.
• Aggressive Exhaust Note
  Enhances the auditory experience of your BMW with a deeper, more refined tone under acceleration—without introducing harsh cabin drone.
• Dyno-Tested Performance Gains
  Gains of 20–30+ horsepower and torque are achievable when combined with supporting mods and ECU calibration.
• includes heavy duty gasket for Free!
• V-Band Flange Type

Product Specs:

• Engine Compatibility: BMW B46 2.0L Turbocharged I4
• Chassis: G20 BMW 320i xDrive (2019+)
• Material: T304 Stainless Steel
• Configuration: Catless (Race Use Only)
• Install: Fully reversible; bolts to stock or aftermarket exhaust systems

Fitment: 

• 2016-2020 F20/F22 BMW 220i, 230i including xDrive (B46 2.0T engine)
• 2016-2020 F30/F31 BMW 320i, 330e, 330i including xDrive (B46 2.0T Engine)
• 2016-2020 F32/F33/F36 BMW 420i, 430i including xDrive Models (B46 2.0T Engine)
• 2016 – 2020 G30 BMW 530i, 530e including xDrive Models (B46 2.0T Engine)
• 2016-2020 G11 BMW 730i, 740e including xDrive Models (B46 2.0T Engine)
• 2019-2023 G20 BMW 320i, 330i including xDrive (B46 2.0T Engine)
• 2019+ G29 BMW Z4 30i (B46 2.0T Engine)
• 2020+ A91 Toyota Supra 2.0 (B46 2.0T Engine)

Installation Note:

Installing catless B46 downpipes will trigger a check engine light (CEL) due to the removal of the OEM catalytic converters. To resolve this, we offer the Spdz1 Mini Cat, which attaches to the O₂ sensors and effectively eliminates the CEL without requiring a tune. 

Why SPDZ1?

As a brand rooted in aftermarket performance and tuning, SPDZ1 knows that the details matter—from how something looks to how it fits and performs. These finishers reflect that mindset: built to be seen, built to last, built for your build.