At each of these, we recorded the pressure increase and plotted these points on a graph to give a visual representation of how the restriction of the filter increases with airflow, therefore allowing a direct comparison between filters. To test the filters, we fitted them to the rig and increased the flow rate at measured increments. We could then compare the data acquired when the filters were tested to get a more accurate performance figure. Before we began, we tested the rig and measured the pressure losses created by the rig itself. The restriction test we came up with was quite straightforward. One thing is certain, though – not all air filters are the same, so we decided to compare a few.

In terms of restriction, running no air filter is always going to be the least restrictive option, but this will allow damaging dirt and debris in, too, significantly reducing the engine’s life.įor this reason, a good performance air filter needs to find that perfect compromise of balancing filtration against airflow. Fitting a less restrictive air filter will allow more air in, therefore giving potential for increased power.Īn air filter’s primary function is to prevent dirt and debris from getting into the inlet system and causing any damage. As the filter is the first part of the inlet system, the amount of air it allows to enter the engine has a direct correlation with how much horsepower the engine can potentially produce. Here, we test six aftermarket cone filters to see which flows the best.įitting a performance air filter is usually one of the first upgrades you will make in the search for increased power.

Performance car air filters are used on almost all tuned cars.

Do k and n filters make a difference