Milltek Cat Back Exhaust - BMW F90 M5 LCI OPF 2021-2025

QT Parts is a Finnish online store.

Our warehouse is located in Nokia, Finland.

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The delivery time for products in stock is 1-5 business days. We ship worldwide.

If the product is not in stock and it is a pre order product, the average delivery time is 5-21 business days. If the product has a longer delivery time than previously announced, we will be in touch. International orders may be subject to VAT, import duties, and customs fees upon arrival in the destination country.

Terms for product returns:

• You must return the ordered products within 14 days of receiving
• The products must be unused and without damages
• Commission fee for handling returns is 21,90€
• For product returns, the customer is in charge of the return costs. Only door to door service (Express)
• Shipping costs are not refunded

For international orders sales are final and non-refundable. Once an order is placed, it cannot be canceled or returned. By placing an order, you acknowledge and agree to these terms.

Return address: QT Parts, Vasarakatu 8B, 37150 Nokia, Finland.

Pre order / made-to-order products

If the product you have ordered is a pre order or made-to-order item, it is not subject to the 14-day right of withdrawal or return under consumer protection laws, as the product is manufactured or sourced specifically based on the customer’s individual order.

If you wish to cancel your order before receiving the product, we will refund 50% of the total order amount.

This condition applies to the following product categories:

• Suspension
• Engine Tuning
• Engine Parts
• Exhaust Systems
• Fueling
• Turbochargers/superchargers
• Drivetrain
• ECE-approved Downpipes

All of the above products are manufactured or sourced individually based on the customer’s order, and therefore cannot be returned after delivery, unless the product has a manufacturing or material defect.

In the event of such a defect, the standard liability for defects as provided by consumer protection legislation shall apply.

The Milltek Sport Cat Back exhaust system is designed for BMW F90 LCI M5 and M5 Competition models equipped with a 4.4-liter twin turbo V8 (S63) engine and a factory-fitted OPF/GPF particulate filter. While the factory system emphasizes comfort and sound dampening, Milltek's Cat Back solution improves exhaust flow and brings out the engine's sound in a controlled yet significantly more sporty manner.

The Cat Back exhaust system replaces the exhaust section after the downpipe, unleashing the engine's sound and improving flow without compromising daily drivability.

Rich and Sporty V8 Sound

Milltek has specifically optimized this system to support the characteristics of OPF/GPF models, offering the following differences compared to the standard system:

• Deeper and clearer V8 sound at idle

• Loud and sporty tone during acceleration

• Controlled yet powerful sound at high RPMs

• No disturbing resonance or drone during highway driving

The soundscape gives the S63 engine's personality the voice it deserves.

Improved Flow and Drivability

The Milltek Cat Back exhaust system offers:

• Lower backpressure for exhaust gases after the OPF/GPF filter

• Improved throttle response

• Better flow characteristics that also support software updates and the benefits of tuning parts

The design supports the engine's natural operating range and complements its performance.

Direct Bolt-on Installation

• To fit directly into the car's original mounting points

• To be compatible with F90 LCI models' drivetrain and chassis

• To be installed without welding or structural modifications

The OEM-level fit ensures hassle-free installation and seamless integration into the car's original structures.

304L Aircraft Grade Stainless Steel

The Milltek Sport exhaust system is manufactured from high-quality 304L grade stainless steel, offering:

• Excellent corrosion and heat resistance

• Long lifespan even under intensive use

• Flow-optimized design

• Precisely finished TIG welds

This material choice meets Milltek's demanding quality and performance standards.

Fitment

• BMW M5 (F90 LCI)

• BMW M5 Competition (F90 LCI)

Engine: 4.4 Twin Turbo V8 (S63)
Only OPF/GPF-equipped cars
Model years 2021–2025

Note! This exhaust system removes the OPFs. This modification also requires a software change. Not for road use.