DCE BMW B58 5.2 Inch Downpipe For G01 X3, G02 X4 M40i & G05 X5, G06 X6, G07 X7 40i

The DCE BMW B58 5.2 Inch Downpipe is a high-performance upgrade engineered for owners of the G01 X3 M40i, G02 X4 M40i, G05 X5 40i, G06 X6 40i and G07 X7 40i models equipped with the OPF and V-Band flange configuration. Available in three versions — Catless, High Flow Sports Cat 200 Cell, and High Flow Sports Cat 300 Cell — this downpipe is designed to unlock significant power gains, faster turbo response, and a dramatically enhanced exhaust tone.

Constructed to exceptional standards and featuring an oversized 5.2-inch (132mm) body including heat shielding, the DCE downpipe maximises exhaust flow while maintaining optimal thermal management. By reducing backpressure, the turbocharger is able to spool earlier and recover boost more quickly after gear changes, delivering sharper throttle response and smoother, more aggressive acceleration. Gains of up to 15hp and 25Nm are typically realised from the downpipe upgrade alone, with even greater improvements available when paired with ECU recalibration.

Whether you choose a full decat for maximum flow, a 200-cell sports cat for high performance while retaining catalytic efficiency, or a 300-cell sports cat for a more OE-like balance, each version is equipped with a premium heat shield and is engineered for a perfect fit on OPF-equipped B58 models.

Note: Catless versions are designed exclusively for off-road use. Sports cat variants may be road legal depending on regional regulations — please check your local laws.

Key Features

• Available in Catless, 200 Cell Sports Cat, or 300 Cell Sports Cat versions

• Oversized 5.2-inch (132mm) body with integrated heat shield

• Reduced backpressure for quicker turbo spool and improved response

• Gains of up to 15hp / 25Nm from the downpipe alone

• Significantly deeper, more aggressive exhaust tone

• Stainless-steel construction for durability and long-term performance

• Designed specifically for OPF & V-Band B58 models

• Compatible with stock and aftermarket exhaust systems

• OE-style fitment for straightforward installation

• ECU remap required for optimal performance on catless systems

Compatibility

Fits BMW B58 OPF & V-Band flange vehicles:

• BMW G01 X3 40iX (2018+)

• BMW G02 X4 40iX (2018+)

• BMW G05 X5 40iX (2018+)

• BMW G05 X5 45eX (2018+)

• BMW G06 X6 40iX (2018+)

• BMW G07 X7 40iX (2018+)

Not compatible with:
Vehicles featuring EU6 RDE II emissions system with dual OPF pressure sensor connections.

Unless explicitly stated otherwise, all products sold by R44 Performance Limited are designated RACE ONLY and are solely for competition or off-road use limited to racing formally sanctioned by a recognized racing organization. Any other use, including recreational off-road use, may violate local, state, and Federal laws. R44 Performance Limited does not implicitly or explicitly confirm the legality of using any products it sells on public roads; that is entirely the responsibility of the consumer.

It is the responsibility of the customer to check with all federal, state local and environmental laws before ordering and installing a product. R44 Performance Limited is not responsible for any fees, fines or costs that a customer may incur as a result of failing to check with federal, state, local or environmental laws before ordering and installing a product.

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