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Exhaust› Catalytic Converters

CTS Turbo

High-Flow Cat B46 Engine

Name: High-Flow Cat B46 Engine
Brand: CTS Turbo
SKU: CTS-EXH-DP-0037

$429.99 $271.59 Save $158.40

SKU: CTS-EXH-DP-0037

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Moderate — 2–4 hours

Overview

The CTS Turbo High-Flow Cat is a downpipe replacement designed to maximize exhaust flow and power gains for North American market BMW B46 engines. It is constructed from T304 stainless steel with TIG welded, back-purged construction for durability. This high-flow cat replaces the restrictive factory downpipe with a 200-cell catalytic converter to improve performance and provide a sporty exhaust sound without drone.

Show original supplier description

Designed using advanced CAD technology, this downpipe is crafted to fit perfectly in place of your original equipment. Constructed from premium T304 stainless steel, the unit features robust hand TIG welding and back-purging to ensure years of reliable performance. It incorporates a high-flow 200-cell catalytic converter, designed to enhance exhaust gas flow while providing a sporty exhaust note without factory exhaust drone. This downpipe is specifically designed for B46 engines found in North American market vehicles. Installation requires careful consideration of fitment. This high-flow cat is intended exclusively for B46 SULEV engines featuring a flange connection to the exhaust. It is crucial to verify your vehicle's downpipe connection and ensure it does not have a GPF/OPF (Gasoline Particulate Filter/Otto Particulate Filter) before ordering, as this downpipe is not compatible with those systems. Additionally, the use of Bootmod3 stage 2 software or similar is strongly recommended to prevent a check engine light (CEL) from illuminating. Catalytic converters damaged by "crackle tunes" are not covered under warranty.

Vehicle Symptoms

Sluggish acceleration and lack of power
Check engine light for catalyst efficiency
Restricted exhaust flow causing poor throttle response
Wanting a sportier exhaust note without drone
Feeling of engine being choked at high RPM

Diagnostic Codes

P0420 – Catalyst System Efficiency Below Threshold (Bank 1)

Relevant Conversations

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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.

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Specifications

Brand	CTS Turbo
Part Number	CTS-EXH-DP-0037
Category	Exhaust

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