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

The delivery time for products in stock is 1-3 business days.

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.

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 (outside of Europe) 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 the BMW F90 LCI M5 and M5 Competition models with the 4.4-liter twin turbo V8 (S63) and factory-fitted OPF/GPF particulate filter . The factory system emphasizes comfort and damping, while the Milltek Cat Back solution improves exhaust flow and brings out the engine sound in a controlled but significantly sportier way.

The Cat Back exhaust system replaces the section of the exhaust system after the downpipe , freeing up engine sound and improving flow without compromising daily drivability.

Rich and sporty V8 sound

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

• Deeper and clearer V8 sound at idle

• Loud and sporty sound during acceleration

• Controlled yet powerful sound at high revs

• No annoying resonance or drone when driving on the road

The soundscape gives the personality of the S63 engine the sonic expression it deserves.

Improved flow and driveability

The Milltek Cat Back exhaust system offers:

• For exhaust gases with lower back pressure after OPF/GPF filter

• Improved throttle response

• Better streaming capabilities that also support software updates and tuning component benefits

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

Direct bolt-on installation

• Fits directly into the car's original mounting points

• Compatible with the F90 LCI powertrain and chassis

• Installable without welding or structural changes

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

304L Aircraft Grade Stainless Steel

The Milltek Sport exhaust system is made from top quality 304L grade stainless steel , offering:

• Excellent corrosion and heat resistance

• Long service life even with intensive use

• Flow-optimized structure

• Precisely finished TIG welds

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

Fit

• 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