COMPATIBLE: (3.0L - B58B30)
2016 - 2021 BMW M240i
2016 - 2021 BMW M240i xDrive
2015 - 2019 BMW 340i
2015 - 2019 BMW 340i xDrive
2016 - 2019 BMW 440i
2016 - 2019 BMW 440i xDrive
2017 - 2024 BMW 540i
2017 - 2024 BMW 540i xDrive
2017 - 2023 BMW 630i
2017 - 2023 BMW 630i xDrive
2017 - 2023 BMW 640i
2017 - 2023 BMW 640i xDrive
2016 - 2022 BMW 740i
2016 - 2022 BMW 740Li
2019 - 2025 BMW 840i
2018 - 2025 BMW X5 xDrive40i
2018 - 2025 BMW X5 sDrive40i
2020 - 2025 TOYOTA GR SUPRA
HIGHLIGHTS
• 6" High-Flow Section
• Improved Exhaust Sound
• Faster Turbo Spool
• Safely Flash Stage 2+ Tunes
• SS304 Stainless Steel
PROFILE
The ARM 6" B58 Downpipe takes the title of being the largest catless downpipe available for the B58 platform! The sound coming from your B58 with the 6" section of the ARM B58 Downpipe will astonish you. Even deeper tones, even better sound, and improved turbo spool.
The ARM 6" B58 Downpipe is one of the foundational upgrades for giving your B58-powered BMW more power, torque, and sound. The stock B58 downpipe comes from the factory with a catalyst that severely restricts exhaust flow, causing excessive backpressure with increased boost. Upgrading to the ARM 6" B58 Downpipe unlocks power, improves turbo spool, allows you to safely run stage 2+ tuning, all while improving the sound of your B58-powered BMW.
ENHANCE THE SOUND OF YOUR B58
The ARM 6" B58 Downpipe will noticeably increase the overall volume of your B58, open up the exhaust burbles even on OEM programming, and make the turbo spool significantly more audible.
CONSTRUCTION
The ARM 6" B58 Downpipe is built with SS304 stainless steel and is TIG welded. The ARM 6" B58 Downpipe starts with a 4.5" diameter precision CNC machined turbo V-band flange which rapidly transitions to the 6" OD high-flow section.
The ARM 6" B58 Downpipe features two O2 sensor bungs to allow for reinstallation of the OEM oxygen sensors. The pre-catalyst O2 sensor bung is located closer to the turbo on the ARM 6" B58 Downpipe to avoid stretching the O2 sensor wires during installation. The post-catalyst O2 sensor bung comes with a built-in extension to allow the sensor to reach around the 6" section of the downpipe.
The ARM 6" B58 Downpipe then reduces to the OEM 3.1" diameter to allow it to connect to the OEM midpipe or the ARM B58 Midpipe Upgrade. The flex section is incorporated into the ARM 6" B58 Downpipe to relieve stress on the turbo during aggressive driving.
The ARM 6" B58 Downpipe is further secured by the 2-bolt bracket which utilizes the OEM downpipe mounting points.
IN THE BOX
• ARM 6" B58 Downpipe
WARRANTY:
