Exhaust› Exhaust Pipes, Systems and Components

Bimmer Network

B58 4.5" Catless Downpipe

$399.99

SKU: BNDPB58

In Stock
In Stock
Ships by Sep 13
Free Shipping over $200
$100 Minimum Order
30 Days Return
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Overview

The BimmerNetwork B58 True 4.5" Catless Downpipe is a high-flow exhaust component designed to reduce backpressure and relieve stress on the turbo. It features a true 4.5-inch diameter piping that maintains its size until it meets the exhaust system.
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The BimmerNetwork B58 True 4.5" Catless Downpipe is engineered for enhanced exhaust flow and turbocharger performance in B58-equipped vehicles. This downpipe boasts a full 4.5-inch diameter that is maintained throughout its length, unlike other products that taper down shortly after the turbo outlet. This design minimizes exhaust restriction, reduces backpressure, and alleviates stress on the turbocharger, potentially leading to improved engine response and performance. For those seeking a custom exhaust setup, it can be cut at the taper and welded to a larger diameter flex joint. The product is explicitly for off-road use only, with a disclaimer stating that installation on a motor vehicle is illegal in most states and that BimmerNetwork does not sell for road use. This downpipe is compatible with all Bmw/Toyota B58-equipped models, specifically covering Gen 1 and Gen 2 B58 engines, including the Toyota Supra MK5. Fitment spans from 2016-2019 models such as the M140i, M240i, 340i, 440i, 540i, 640i GT, and 740i. It also fits 2019-2020 models like the Z4 M40i and GR Supra 3.0. The compatibility extends to 2020-Present models across various BMW series including the 3 Series (M340i), 4 Series (M440i), 5 Series (540i LCI), 6 Series GT (640i GT), X5 (xDrive40i, sDrive40i), X6 (xDrive40i, sDrive40i), X7 (xDrive40i), 7 Series (740i LCI), 8 Series (840i), and the 2 Series (M240i), as well as the 2021+ Toyota Supra 3.0 and Z4 M40i.

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

BrandBimmer Network
Part NumberBNDPB58
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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