ARM Motorsports

B58 DOWNPIPE - 240I 340I 440I 540I 640I 740I

B58 DOWNPIPE - 240I 340I 440I 540I 640I 740I
B58 DOWNPIPE - 240I 340I 440I 540I 640I 740I
B58 DOWNPIPE - 240I 340I 440I 540I 640I 740I
B58 DOWNPIPE - 240I 340I 440I 540I 640I 740I
B58 DOWNPIPE - 240I 340I 440I 540I 640I 740I
B58 DOWNPIPE - 240I 340I 440I 540I 640I 740I
B58 DOWNPIPE - 240I 340I 440I 540I 640I 740I
B58 DOWNPIPE - 240I 340I 440I 540I 640I 740I
B58 DOWNPIPE - 240I 340I 440I 540I 640I 740I
B58 DOWNPIPE - 240I 340I 440I 540I 640I 740I
B58 DOWNPIPE - 240I 340I 440I 540I 640I 740I
B58 DOWNPIPE - 240I 340I 440I 540I 640I 740I
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• Increase Power and Torque
• Faster Turbo Spool
• Improved Exhaust Sound
• Safely Flash Stage 2+ Tunes
• SS304 Stainless Steel


The ARM 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 your downpipe unlocks power, improves turbo spool, allows you to safely run stage 2+ tuning, all while increasing the sound of your B58-powered BMW.   


The ARM B58 Downpipe will increase the overall volume of your BMW, open up the exhaust burbles even on OEM programming, and make the turbo spool significantly more audible.  The M240i in the video below is only equipped with the ARM B58 Downpipe, it is otherwise on a 100% stock exhaust. The car has never been flashed, it is on the original DME programming from BMW.  


The ARM B58 Downpipe is built with SS304 stainless steel and backed by the ARM Motorsports Lifetime Warranty.  The ARM B58 Downpipe starts with a 4.5" diameter precision CNC machined turbo v-band flange

B58 Downpipe

The ARM B58 Downpipe then gradually reduces to a 3.1" diameter before the flex section.  The flex section is incorporated into the ARM B58 Downpipe to relieve stress on the turbo during aggressive driving.

B58 Downpipe

The ARM B58 Downpipe is further secured by the 2-bolt bracket which utilizes the OEM downpipe mounting points.

B58 Downpipe

The 3.1" diameter continues after the flex section to allow for an easy installation to the OEM midpipe, or any midpipe that connects to the OEM B58 downpipe.    

The ARM B58 Downpipe features two O2 sensor bungs to allow for reinstallation of the OEM oxygen sensors.  The O2 sensor bungs are located closer to the turbo on the ARM downpipe to avoid stretching the O2 sensor wires during installation.  A tune or CEL Delete will be required to avoid a check engine light from displaying on instrument panel.

B58 Downpipe



 By improving the exhaust flow on your B58 BMW with the ARM B58 Downpipe, you're prepared for the higher boost tunes.  If you already have a software program for your B58 chances are these tune files are already pre-loaded into your software waiting for you to flash after your downpipe is installed.  Most tunes require an upgraded downpipe to run properly.


• ARM B58 Downpipe


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



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.

We have a 30-day return policy, which means you have 30 days after receiving your item to request a return.

To be eligible for a return, your item must be in the same condition that you received it, unworn or unused, with tags, and in its original packaging. You’ll also need proof of purchase.

To start a return, you can contact us at If your return is accepted, we’ll send you instructions on how and where to send your package. Items sent back to us without first requesting a return will not be accepted.

You can always contact us for any return question at

Damages and issues
Please inspect your order upon reception and contact us immediately if the item is defective, damaged or if you receive the wrong item, so that we can evaluate the issue and make it right.

Exceptions / non-returnable items
Certain types of items cannot be returned, Burger Motorsports does not allow returns, custom products (such as special orders or personalized items), and air filters can not be returned. We also do not accept returns for hazardous materials, flammable liquids, or gases. Please get in touch if you have questions or concerns about your specific item.

Unfortunately, we cannot accept returns on sale items or gift cards.

The fastest way to ensure you get what you want is to return the item you have, and once the return is accepted, make a separate purchase for the new item.

We will notify you once we’ve received and inspected your return, and let you know if the refund was approved or not. Certain circumstances will require a restocking fee of up to 25% at the discretion of Palenon Performance. (Examples of these circumstances include but are not limited to multiple failed delivery attempts, modified or damaged products and packaging, etc.) If approved, you’ll be automatically refunded on your original payment method. Please remember it can take some time for your bank or credit card company to process and post the refund too.


If the item is shipping from us direct, you will receive a tracking number within 1 business day. Most orders fulfilled at our warehouse will ship the same business day if ordered by 12pm MST. If the item is being drop shipped from the manufacturer, we cannot guarantee a tracking number within 1 business day. If an item is being drop shipped, we cannot guarantee the 24 hour (1 business day) processing time. A purchase of expedited shipping at checkout means that once item is ready to ship, it will ship using the upgraded shipping method. Some manufacturers require 3-5 days to process orders. Purchasing expedited shipping may speed up the processing time of your order, but we cannot make any guarantees in relation to faster processing time on the manufacturer’s end.


If you used a credit/debit card or PayPal to place an order and decide to cancel or return your order for any reason, a 5% merchant fee will be passed along to you (8% for Shop Pay installments). Some manufacturers can take up to 7 business days to ship out orders. If an item is out of stock we will reach out to you within 48 hours to confirm you would like to proceed with a preorder. If the item is listed as custom-built/ built to order within the description, or if the ETA or average lead time is visible on the product page at the time of ordering and you are cancelling inside of that ETA/lead time you will be charged the merchant fee. If the cancellation is outside of the time frame the merchant fee will not be charged to you for canceling. 

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