Another way to improve the air intake is to considerably shorten the ducting system by removing the closed airfilter box (difficulty of changing the filter element) including the long tube and change to an open airfilter system directly fitted to the intake manifold (K&N 57i Induction System Ford Fiesta 2008-2011 1.6L) via an Samco elbow (45/60mm); no relocation of the MAF-sensor.
You can add a cold air ducting system (intake funnel fixed at the bottom side of the radiator) directed to the open air filter.
I did the conversion with good results (better sound and torque without loss of driveability).
Pictures on request ( dherdebart@telenet.be)
I was also thinking about an open system but I did not want more noise. Car makers not always construct items which are not good performing. An air filter housing is not only made to restrict airflow (and noise) as one could think, it may help to improve the airflow.
Watch this video and see what happens performance wise without the filter housing in comparison when the car (in this case) is significantly slower accelerating:
http://youtu.be/lDnptzZBrUMI have a hose fitted to the bottom of the filter box which leads to the front below the radiator. So all air in the box is cool.
I have not tested a short path system until now, I will do later on, but I'm wondering how it could improve low rev torque.
