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ARM Motorsports

ARM 6" B58 DOWNPIPE - M240i 340i 440i 540i 640i 740i

ARM 6" B58 DOWNPIPE - M240i 340i 440i 540i 640i 740i

Regular price $397.00 USD
Regular price Sale price $397.00 USD
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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.  
B58 6in Downpipe
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

B58 Downpipe



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
 

FITMENT GUIDE

Make Model Submodel Engine
BMW F22 M240i B58 3.0L
BMW F22 M240i xDrive B58 3.0L
BMW F23 M240i B58 3.0L
BMW F23 M240i xDrive B58 3.0L
BMW F30 340i B58 3.0L
BMW F30 340i xDrive B58 3.0L
BMW F32 440i B58 3.0L
BMW F32 440i xDrive B58 3.0L
BMW F33 440i B58 3.0L
BMW F33 440i xDrive B58 3.0L
BMW F34 340i xDrive B58 3.0L
BMW F36 440i B58 3.0L
BMW F36 440i xDrive B58 3.0L
BMW G30 540i B58 3.0L
BMW G30 540i xDrive B58 3.0L
BMW G32 640i B58 3.0L
BMW G32 640i xDrive B58 3.0L
BMW G12 740i B58 3.0L
BMW G12 740i xDrive B58 3.0L
BMW G15 840i B58 3.0L
BMW G15 840i xDrive B58 3.0L
TOYOTA A90 Supra B58 3.0L
TOYOTA A91 Supra B58 3.0L
 

ARM MOTORSPORTS LIFETIME WARRANTY

Every ARM Motorsports product is backed by a lifetime warranty which is automatically issued at the time of purchase. Your warranty protects you against any defects in craftsmanship or fitment. The warranty entitles you to a replacement unit.

This product is for Off-Road Use Only. Items sold for off-road use only are illegal to use on public roads in most states and provinces. This product is intended for racing vehicles which may never be used on a public road.
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