What gain can there be from replacing the original air filter for one that allows a better air flow?
Are these improved filters safe? (do they stop all the particles that can harm the engine?)
I am about to upgrade the ECU of my xantia HDi. What would be the impact of using a competition or alternative air filter? And the impact of keeping Citroen's filter?
Thanks,
Best regards
Improving the air filter
Moderator: RichardW
I can only give you the experience from my competition days and I don't think physics have changed that much since.
Competition air filters are designed to allow air through at higher volumes with less pressure drop either side of the filter. They can only do this by either increasing the surface area available for the air to pass which means a larger filter or by increasing the pore size of the filter medium.
So if its the same size then the pore size is larger = larger lumps getting through or larger physical dimension = greater airflow.
The next point is that the air flow is really only critical at higher engine speeds when the volume of air required increases beyond the capability of the filter medium to avoid increasing the pressure drop on the engine side of the filter.
In normal driving I suspect you would not gain any difference. Others may have a differing opinion. Robin
Competition air filters are designed to allow air through at higher volumes with less pressure drop either side of the filter. They can only do this by either increasing the surface area available for the air to pass which means a larger filter or by increasing the pore size of the filter medium.
So if its the same size then the pore size is larger = larger lumps getting through or larger physical dimension = greater airflow.
The next point is that the air flow is really only critical at higher engine speeds when the volume of air required increases beyond the capability of the filter medium to avoid increasing the pressure drop on the engine side of the filter.
In normal driving I suspect you would not gain any difference. Others may have a differing opinion. Robin
