BMW B58 Spool 4.5" Stainless Race Downpipe

The Spool 4.5 inch race downpipe for the BMW B58 cuts backpressure on the turbo and is built with fewer welds where downpipes usually crack.

Why you need it

A downpipe is one of the best value mods on a turbo BMW. Lower backpressure lets the turbo build boost more efficiently and puts less stress on it, and with a tune the power gains are big. Spool avoids a weld right before the turbo flange, a high-stress area where many downpipes fail, and uses a highly flexible flex section so lining it up with your exhaust is much easier at home.

Fits

• All Gen 1 and Gen 2 B58 engines (2 port and 6 port)
• 2016+ BMW M240i & M240i xDrive (F22/F23)
• 2016+ BMW 340i & 340i xDrive (F30/F31)
• 2016+ BMW 440i & 440i xDrive (F32/F33/F36)
• 2016+ BMW 540i & 540i xDrive (G30)
• 2016+ BMW 740i & 740i xDrive (G11/G12)
• 2017+ BMW X3 M40i (G01)
• 2018+ BMW X4 M40i (G02)
• 2019 to 2023 BMW M340i & M440i incl. xDrive (G20/G22/G26)
• 2021 to 2023 BMW M240i & M240i xDrive (G42)
• 2019 to 2023 BMW X5 xDrive40i (G05)
• 2019 to 2023 BMW X6 xDrive40i (G06)
• 2019 to 2023 BMW X7 xDrive40i (G07)
• 2019 to 2023 BMW Z4 M40i (G29)
• 2019 to 2023 BMW 840i & 840i xDrive (G14/G15/G16)
• 2022+ BMW 740i & xDrive (G70)

Features

• 4.5 inch 304 stainless steel construction
• Smooth transitions for maximum flow
• No weld right before the turbo flange
• Highly flexible flex section for easier alignment
• More aggressive exhaust note

Good to know

Power gains depend on a supporting tune. This part modifies or replaces emissions equipment. Intended for off-road and competition use only. Not legal for use on public roads in many areas.