Air filters are not just servicing items - they're a vital part to improving your MINI's performance
Air filters are a vital component of any engine to provide a consistent supply of clean air to the combustion process. Air filters in the MINI are typically paper filters. Paper filters offer relatively good filtration at a low cost, however suffer from clogging after prolong use. Using aftermarket foam or cotton gauze as the filtration material on air filters has several benefits over paper filters:
- Airflow is optimised
- Filtration is optimised
- Oil covering provides an additional filtration element
- Greater tolerance to clogging
- Re-useable
By increasing airflow delivered to your MINI’s engine, you’re helping to increase performance. Foam panel filters from ITG or cotton gauze filters from K&N have vastly superior airflow over the standard paper filter fitted to the MINI. 
In addition to improving the filtration material another method of improving airflow is by increasing the surface area of the filter or improving the flow of air across the filter. Induction kits such as the AEM Intake Kit for the MINI do just this. By utilising the bonnet scoop on the Cooper S and having an enlarged filter head, the AEM intake can deliver huge power gains as we saw on our in-house dyno. 
Filtration is superior when using cotton and foam filters. Foam filters from ITG use a TriFoam System that has various thicknesses of gradually finer foam to remove debris, extracting particles down to 5 microns in size. Both cotton gauze filters from K&N and foam filters from ITG have an oil coating that adds a sticky element to the filter acting as an extra filtration media and also has the benefit of providing a hydrophobic (water repelling) layer to the filter. Improved filtration means increased protection for the engine. 
Foam filters have an improved resistance to clogging so maintaining their higher level of performance for longer and greater service intervals. Foam and cotton gauze filters are reusable resulting in long-term savings as well as greater performance and being more environmentally friendly. Cleaning the filter can be done at home but does require a specialist cleaner and specialist oils to be reapplied – Lohen can supply these when it comes to servicing time. To clean the filter remove the panel filter or cone from the car and simply spray over the air filter cleaning fluid and allow to stand for 5-10 minutes then rinse off with water. The filter will need to be allowed to dry naturally. Once dry apply the air filter oil dust retention coating and then install back on the car. You'll find details of the Pipercross Cleaning Kit here.
