the svt has two openings to the lower part of the intake box. one is the S shaped part on the right, the other is the scoop by the front of the hood. SVT reasoned that because the SVT motor breathed much better, it needed to suck in more air, but one of their intake locations was not thought out very well. the majority of the air comes from the scoop at the very front of the car. on the standard zetec engine, they have a sealed box instead of the S shaped intake on the right. as that the standard zetec was not designed to need more air than the front scoop supplied, the box slows the air down as it enters the intake, causing a loss of performance. the SVT scoop is bigger, but SVT thought it still needed more air (or else they just wanted to make the intake louder), so they put the S shaped snorkel on there.