BMW 4 Series (F32/F33/F36) Catless Downpipe – High-Flow Stainless Steel Design for Enhanced Turbo Response & Performance | Fits 418i, 420i & 430i Coupe, Convertible & Gran Coupe Models – B46 2.0L Turbo Engine (2016–2019)

Unlock the hidden performance of your BMW 4 Series (F32/F33/F36) with the BAVMODS® Catless Downpipe — precision-engineered for the B46 2.0L TwinPower Turbo engine to improve exhaust flow, boost response, and deliver a deep, motorsport-inspired exhaust tone.

The factory catalytic converter in the B46 engine is highly restrictive, trapping heat and slowing turbo response. The BAVMODS® Catless Downpipe removes this bottleneck completely — freeing up the exhaust path to reduce backpressure and increase efficiency across the rev range. The result is quicker spool, sharper throttle response, and improved midrange power that transforms the way your 4 Series performs and sounds.

Engineered for Maximum Flow & Durability

Built from premium T304 stainless steel, each downpipe is mandrel-bent for consistent internal diameter and TIG-welded by hand for superior strength and precision. Every unit includes factory-positioned O₂ sensor ports, reinforced flanges, and an integrated heat shield section to protect nearby components from excess heat while maintaining OEM+ fitment.

Key Performance Benefits

• Free-Flow Straight-Pipe Design: Removes the restrictive factory catalytic converter to maximize exhaust velocity.
• Sharper Throttle Response: Reduces backpressure, allowing boost to build faster and stronger.
• Dyno-Proven Gains: Noticeable horsepower and torque improvements with a proper Stage 2 ECU tune.
• Aggressive Exhaust Tone: Deep, clean sound under load with turbo spool and refined burbles.
• Thermal Control: Integrated shielding and T304 construction reduce radiant heat and maintain reliability.
• OEM+ Fitment: Direct bolt-on design compatible with both stock and aftermarket exhaust systems.

Installation & Compatibility

Includes all gaskets, clamps, and hardware for a true plug-and-play installation — no cutting, welding, or modification required. Pair with a Stage 2 ECU tune for optimal performance and to prevent CEL illumination.

Performance You Can Feel

Experience smoother throttle transitions, improved spool times, and an aggressive yet refined exhaust tone. The BAVMODS® Catless Downpipe unleashes your 4 Series’ full potential — designed for enthusiasts who demand both performance and precision.

FITMENT: BMW 4 Series (F32 Coupe / F33 Convertible / F36 Gran Coupe) – 418i, 420i, 430i (2016–2019)

ENGINE COMPATIBILITY: B46 2.0L TwinPower Turbo Inline-Four

NOTE: For off-road or competition use only. Always verify your vehicle’s engine code and production year before installation.

Please refer to the “Fitment” section in the product description for compatibility details.