Air Filters & Wraps

Does your old air filter need replacing, or is your open intake missing a filter with the right flange? Here we bring together replacement filters, universal filters, and filter wraps and pre-filters for you who want to keep your engine's intake air clean. They suit daily driving, track days and bigger projects alike.

Replacement filter or universal filter?

A replacement filter replaces the filter in a specific airbox or intake, e.g. the COBB filter for HCT intakes. A universal filter is typically clamped directly onto an intake pipe and is chosen by dimensions rather than car model. Examples include the Airaid cone filter with a 4-1/2 inch flange and the Corsa filters in the Primo and Pro5 series. A wrap or pre-filter goes over the outside of the filter and can keep water and coarse dirt out.

How to choose an air filter

• Fitment: For the airbox, the part number must match exactly. For universal filters, the flange's inner diameter, the length and the space in the engine bay are decisive.
• Filter media: Oiled cotton, dry synthetic material and foam differ in filtration, airflow and maintenance.
• Placement: An open filter close to the engine can draw in hot air. Consider a heat shield or a solution from intakes and airboxes.
• Airflow demand: A larger filter does not automatically give more power. The demand depends on the engine, boost pressure and the rest of the intake.

Installation and maintenance

A replacement filter is typically placed in the existing airbox, while a universal filter is usually secured with a hose clamp. Washable filters are cleaned according to the manufacturer's instructions. Oiled filters should be re-oiled sparingly, as too much oil can settle on the mass airflow sensor. A pre-filter or filter wrap can extend the interval between cleanings. Brands in the category include K&N Engineering, aFe, BMC, Uni Filter and ProFilter. You will find more intake and fuel parts under air and fuel delivery.

Frequently asked questions

What is the difference between an oiled and a dry air filter?

An oiled filter uses oil in the filter media to trap dirt and must be re-oiled after washing. A dry filter is cleaned without oil. Which suits you best depends on driving conditions, maintenance and the specific product.

How do I measure for a universal filter?

Measure the outer diameter of the pipe the filter will be mounted on. This corresponds to the flange's inner dimension. Also check the filter's length and largest diameter against the space in the engine bay, so the filter does not touch other parts.

Does a performance air filter give more power?

A performance air filter can provide freer airflow, but the gain depends on the engine and the rest of the intake. On many stock engines the difference is limited, while a project with higher boost pressure typically has a greater airflow demand.

How often should a washable air filter be cleaned?

It depends on the manufacturer's instructions and how dusty your driving conditions are. If you often drive on gravel roads or on track, you should check the filter more often. A pre-filter can keep the coarsest dirt out and extend the interval.