B58 Downpipe Upgrade 2017 – 2022 BMW X3 M40iX G01 & X4 M40iX G02

We are proud to introduce our CarbonList race & catted downpipe for your B58 X3 M40iX & X4 M40iX. This downpipe is THE best bang-for-the-buck mod available. It is offered in both race and catted configurations.

By eliminating the restrictive catalytic converter in the factory downpipe, our race or high-flow 200-cell race cat significantly reduces back pressure, resulting in faster spool, increased power, and a more aggressive exhaust note.

Our downpipe features a full 4.5″ stainless steel design and a CNC 304-grade stainless steel flange, ensuring a smooth transition from the turbo to the mid-pipes. All CarbonList downpipes are hand-crafted from SS304-grade stainless steel and include a “No Hassle” satisfaction guarantee (includes fitment).

⚠️ Please note: The warranty on the catted downpipe is limited to two years.

CarbonList 4.5″ BMW X3 M40iX G01 & X4 M40iX G02 B58 Stainless Steel Downpipe

✅ Made from hand-crafted, TIG-welded 4.5″ 304-grade stainless steel.

✅ Available with a 200-cell high-flow cat.

✅ Fits RHD and LHD models with no modifications necessary.

✅ Smooth radius bends to decrease turbulence and increase flow.

✅ Compatible with stock cat-back and all aftermarket cat-backs.

✅ Gains of 25-30 HP with tune.

This item fits the following BMWs:

🚗 2017 – 2022 G01 BMW X3 M40iX xDrive

🚗 2017 – 2020 G02 BMW X4 M40iX xDrive