4.5 Inch SS304 Stainless B58 Downpipe for BMW 2016+ M240i 340i 440i 540i 740i 840i incl. xDrive

Product Overview

This 4.5 inch SS304 stainless steel downpipe is designed as an upgrade for B58-powered vehicles. The title lists 2016-onwards BMW M240i, 340i, 440i, 540i, 740i and 840i models including xDrive, while the specification field names the 2020+ Toyota GR Supra A90 instead. Because of this conflict, please confirm fitment with us before ordering. It is intended for motorsport and off-road use.

Key Features and Benefits

• 4.5 inch (114.3 mm) downpipe diameter
• SS304 stainless steel
• Designed for the B58 engine
• Upgrade for factory downpipe
• New condition retrofit part

Vehicle Compatibility

The title names 2016+ BMW M240i, 340i, 440i, 540i, 740i and 840i including xDrive. The specification field lists the 2020+ Toyota GR Supra MKV A90 3.0L B58. These do not match, and whether catalytic converters are included is not stated. Fitment is supplier-stated and unverified, and must be confirmed before purchase.

Product Specifications

• Product type: downpipe
• Diameter: 4.5 inch (114.3 mm)
• Material: SS304 stainless steel
• Engine: B58
• Condition: new
• Packed size: 65 x 20 x 11 cm
• Packed weight: approximately 3.1 kg

Installation and Usage

A specialist exhaust or performance workshop should install this downpipe. Remove the factory downpipe, transfer oxygen sensors and align the new pipe with the turbo outlet and mid-pipe. Engine calibration is likely required. After fitting, check all joints for leaks, verify clearance from heat-sensitive parts and recheck fasteners after several heat cycles.

Package Contents

Downpipe as pictured. Gaskets, clamps and hardware have not been itemised by the supplier.

Important Fitment Notice

This part is intended for motorsport and off-road use. In New Zealand, altering or removing factory emissions equipment on a road vehicle can breach emissions rules and cause a Warrant of Fitness failure, and exhaust noise limits apply. Please send us your VIN before ordering so we can help confirm fitment. Please include your exact model, build date and any existing tune when you contact us, as this downpipe listing contains conflicting vehicle information.