BMW B58 Gen 3 Spool 4 Inch Race Downpipe

The Spool race downpipe for the BMW Gen 3 B58 uses a full 4 inch design and a precision-machined stainless V-band transition to get exhaust out of the turbo with as little restriction as possible.

Why you need it

Many downpipes neck down near the turbo. This one holds a consistent diameter with a true 3D profile to keep exhaust velocity up, which means sharper throttle response, quicker turbo spool, less lag and a more aggressive exhaust tone. It is built from 304 stainless steel for heat and corrosion resistance.

Fits

• BMW models with the Gen 3 B58 engine

Features

• 4 inch design with no taper at the turbo
• Precision CNC-machined stainless V-band transition for a tight seal
• True 3D profile to maintain exhaust velocity
• 304 stainless steel construction

Good to know

Fitment on 2025 B58 models is not guaranteed. Check your parts diagram or confirm with your VIN before ordering. A supporting tune is needed to use the extra flow. Intended for off-road and competition use only. Not legal for use on public roads in many areas.