MAD BMW F & G Chassis 5" B58 Catted Downpipe M240 340 M340 440 M440 540 W/ No CEL Guarantee & Bracket

Upgrade your stock B58 downpipe to the MAD B58 Catted Downpipe for more power, better sound, and guaranteed reliability without triggering a check engine light.

The MAD Catted B58 Downpipe is the ideal performance upgrade for BMW owners who want more out of their car without the hassle. It's made from premium 304 stainless steel and built to handle extreme heat and tough driving conditions.

The smooth piping design allows for maximum exhaust flow, which translates into more horsepower, better torque, and sharper throttle response. The 300-cell high-flow catalytic converter gives you noticeable gains and a more aggressive sound, all while keeping the check engine light off.

Installation is simple with a direct bolt-on fit to the stock exhaust system. No cutting or welding needed. It's also fully compatible with most aftermarket exhaust setups, giving you the flexibility to build the setup you want.

No check engine light guarantee
If you get a CEL related to the catalytic converter, MAD will replace the downpipe for free.

Warranty coverage

• 1-year warranty on the catalytic converter

• Lifetime warranty on the downpipe for defects and fitment

Race use only

Features

• No CEL guarantee or it's replaced free

• Compatible with right-hand drive and left-hand drive vehicles

• Smooth bends for maximum airflow without drone

• Gains up to 30 horsepower on stock turbos and even more with upgraded ones

• Lifetime warranty on the downpipe

• 1-year warranty on the catalytic converter

• 90-day return policy

• Ships in 1 to 2 business days

• Direct bolt-on fitment

• Flex section for durability

• 300 cell high-flow catalytic converter