R44 BMW F Series B58 Exhaust 200 Cell Sports Cat Downpipe (M140i, M240i, 340i, 440i, G30 540i & more)

The R44 BMW F Series B58 200 Cell Sports Cat Downpipe is engineered to deliver a strong balance of improved exhaust flow, enhanced sound and dependable everyday performance for B58-powered BMW models. Manufactured from high-quality stainless steel, this downpipe replaces the restrictive factory catalytic converter with a high-flow 200 cell sports catalyst, significantly reducing back pressure while retaining a more controlled and refined exhaust note compared to a full catless setup. An integrated heat shield ensures effective thermal management and long-term durability, all delivered with R44’s focus on precise fitment and sensible pricing.

Key Features

• High-grade stainless steel construction

• High-flow 200 cell sports catalytic converter

• Integrated heat shield for improved thermal protection

• Reduced exhaust back pressure versus OEM

• Faster turbo spool and improved throttle response

• Enhanced exhaust tone without excessive harshness

• Increases tuning potential of the B58 engine

• Supplied with a 1 year R44 Performance warranty and fitment guarantee

• Engineered for accurate fitment across a wide range of B58-powered BMW models

Important Disclaimer – Motorsport-Use Recommended

While this downpipe retains a sports catalytic converter, fitment may still breach emissions and noise regulations depending on vehicle specification, tuning level and regional legislation. Vehicles fitted with a 200 cell sports cat downpipe may fail a UK MOT test, particularly when combined with aftermarket software.

Installation may trigger an engine management light, and custom coding or aftermarket tuning may be required to ensure correct operation. R44 recommends this product primarily for motorsport-use or closed-course applications and advises customers to check local regulations before installation.

Compatibility

• BMW M140i (F20 / F21)

• BMW M240i (F22 / F23)

• BMW 340i (F30 / F31)

• BMW 440i (F32 / F33 / F36)

• BMW G30 540i

• Other BMW models equipped with the B58 engine - get in touch for fitment confirmation

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.

We get a large number of custom orders and requests everyday, so as a result it is not always possible for us to keep every item in stock at all times in our warehouse. If you require the item urgently please contact our sales team here to check the stock before you make your purchase.

We totally understand if you're not certain a part will be compatible with your car, so we highly recommend contacting us here with your query. Our friendly sales team will then be in touch to confirm if this part is the correct part you are looking for.

All in stock products ship the same day if ordered before 2pm GMT

For out of stock items we will contact you with an estimated wait time if not otherwise specified above.

We offer worldwide shipping on all products. If upon receiving your product you wish to return; we offer a 30-day returns policy. For our in-depth returns information please follow the link. "R44 Returns Policy

All of our products come with a standard warranty of 1-3 years. This is dependant on the type of product however. For more details please see our warranty page here.