The COBB 13+ Ford Focus ST Air Filter is designed for the verified vehicle applications listed below. Match manufacturer part number 791101, complete year, make, model, application, engine and transmission configuration, required calibration, emissions eligibility, interfaces, and every product note before ordering.

Key Features

• High-Flow Media: Proprietary oiled multi-layer cotton gauze flows 59.2% more air than stock at 3,000 CFM for improved engine breathing.
• Drop-In Fit: Precision-shaped to match OEM housing, ensuring seamless installation and secure seal on 2013-2018 Focus ST.
• Reusable Design: Washable and re-oilable with Cobb filter service kit for repeated use and cost savings over disposables.
• Performance Gains: Dyno-tested to deliver quicker acceleration and efficiency without ECU changes.
• Durable Construction: High-quality rubber flanges and wire mesh support resist tearing for long-term reliability.
• Requires Cobb SF Filter Oil and Cleaner for maintenance every 15,000-30,000 miles.

Fitment

Specifications

What’s Included

One new COBB product in the exact configuration and quantity identified by manufacturer part number 791101. Calibrations, hardware, hoses, clamps, gaskets, adapters, wiring, fluids, tools, and companion components are included only when expressly stated for this exact part number.

About COBB

COBB develops engine-management, intake, cooling, exhaust, drivetrain, suspension, and vehicle-accessory products for supported performance platforms. Correct selection remains exact-vehicle, exact-configuration, exact-interface, and exact-part-number specific.

Related COBB Products

• COBB High Flow Filter – 2014-2019 Ford Fiesta ST
• Cobb Ford F-150 EcoBoost Raptor / Limited / 3.5L / 2.7L High Flow Air Filter
• Ford Focus ST Stage 1 Power Package w/V3

Browse the COBB collection for related tuning, intake, cooling, exhaust, drivetrain, and chassis products.

Frequently Asked Questions

Will this COBB product fit my 2013-2015 Ford Focus ST?
That application is listed, but confirm the exact part number, engine and transmission configuration, factory equipment, required calibration, emissions eligibility, and every manufacturer note before ordering.

Are all supporting parts included?
Only components expressly listed for the exact manufacturer part number are included. Tuning, hardware, hoses, clamps, gaskets, adapters, wiring, fluids, and companion components may be separate.

Is tuning or calibration required after installation?
Requirements depend on the exact product and vehicle. Intake, fuel, boost, turbo, and engine-management changes may require a compatible calibration before operation.

Installation Instructions

Follow the current COBB and factory service instructions for this exact part number. Verify fitment, factory equipment, emissions eligibility, required calibration, software and firmware, interfaces, hardware, fluid or electrical connections, and clearances before installation. Inspect the completed work and confirm safe operation before full-load use.