Milltek Ford Focus MK4 ST Resonated GPF/OPF Bypass | SSXFD311
Milltek Ford Focus MK4 ST Resonated GPF/OPF Bypass – SSXFD311
Upgrade your Ford Focus MK4 ST 2.3 EcoBoost with the Milltek Sport Resonated GPF/OPF Bypass, designed to improve exhaust gas flow and deliver a more distinctive performance exhaust note.
Manufactured in the UK using premium stainless steel, this high-quality Milltek exhaust upgrade replaces the factory Gasoline Particulate Filter (GPF/OPF) with a freer-flowing resonated section.
The resonated (quieter) design offers a more refined exhaust sound compared with non-resonated bypass options, making it ideal for motorsport enthusiasts wanting a sportier exhaust character without opting for the loudest configuration.
Specifically engineered for use with a Milltek Sport Cat-Back Exhaust System, the SSXFD311 offers precision fitment and high-quality construction.
Key Features & Benefits
Milltek Sport Performance Engineering – Premium British-made exhaust components.
Resonated (Quieter) Design – A more controlled exhaust note compared with non-resonated versions.
Improved Exhaust Flow – Removes the restrictive factory GPF/OPF for motorsport applications.
Premium Stainless Steel – Durable, corrosion-resistant construction.
76.2mm (3-inch) Diameter – Large-bore exhaust design.
Milltek Cat-Back Compatible – Designed specifically for connection to compatible Milltek Sport exhaust systems.
Performance Tuning Compatible – Requires a suitable Stage 2 ECU remap.
Vehicle Compatibility
Ford Focus MK4 ST 2.3 EcoBoost Hatchback (GPF/OPF equipped, 2019 onwards)
Ford Focus MK4 ST 2.3 EcoBoost Estate (GPF/OPF equipped, 2019 onwards)
Product Specifications
Manufacturer: Milltek Sport
Part Number: SSXFD311
Product Type: Resonated GPF/OPF Bypass
Pipe Diameter: 76.2mm / 3 inches
Exhaust Configuration: Resonated (Quieter)
Compatibility: Milltek Sport Cat-Back Exhaust
EC Approved: No
ECU Remap: Stage 2 required
Application: Motorsport / off-road use only
Why Choose OC Motorsport?
At OC Motorsport in Battlesbridge, Essex, we specialise in Ford performance upgrades, exhaust systems, professional installation and ECU remapping.
Whether you're upgrading your Focus ST exhaust or planning a complete performance build, our experienced team can help you select compatible components for your vehicle.
Contact OC Motorsport today for product enquiries, compatibility advice and professional fitting options.
Important: This product removes factory emissions-control equipment and is intended for motorsport/off-road use only. It is not suitable for use on UK public roads. A Stage 2 ECU remap is required. This product is designed for fitment to a compatible Milltek Sport cat-back system, not the original factory cat-back exhaust.


