Sale

ARM Motorsports

N20 Downpipe

$227.00 $217.00 Save $10.00

SKU: N20DP

In Stock
In Stock
Ships by Sep 12
Free Shipping over $200
$100 Minimum Order
30 Days Return

Description

The ARM N20 Catless Downpipe is a crucial hardware upgrade for N20 engine owners looking to maximize performance. The stock downpipe significantly restricts exhaust flow, limiting power output and preventing optimal tuning. This upgraded downpipe alleviates excessive back-pressure, unlocking more power, faster turbo spool, and enabling Stage 2+ tuning. It also enhances the exhaust note. Constructed from SS304 stainless steel with mandrel-bent tubing, the ARM N20 Downpipe features a 4-inch diameter at the turbo v-band connection that tapers to 2.5 inches to match the stock mid-pipe. It includes two O2 sensor bungs to accommodate OEM sensors. A tune or CEL delete is required to prevent a check engine light. ARM Motorsports backs this downpipe with a Lifetime Warranty. Please note, this product is for Off-Road Use Only and is intended for racing vehicles. When installed on a 328i with a Stage 1 tune, testing showed gains of up to 17whp and 25wtq. With a Stage 2 tune, an additional 13whp and 12wtq were observed, for a total gain of 30whp and 38wtq over Stage 1 alone. The downpipe also noticeably increases the volume of the exhaust note under full throttle and moderately at part throttle when paired with the stock mid-pipe and cat-back section. It is designed to connect to any aftermarket exhaust compatible with the stock N20 downpipe.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

BrandARM Motorsports
Part NumberN20DP
CategoryExhaust

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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

Free shipping over $200 in the continental US. Alaska, Hawaii, U.S. territories (Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands), and international orders carry surcharges — most appear at checkout. Some exceptions (LTL freight, or suppliers who quote freight only after we place the order) won’t. In those cases we’ll reach out with the exact charge before your order moves forward.

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