[JMPRO]

I read somwhere that the Porsche engineers idea was that the tire rotating in the fender caused a vortex of air that followed the tire. This caused a rush of air behind the oil cooler causing a low pressure area behind the cooler therefor a high pressure area in front of the cooler . This would help to max the flow of air in a simingly confined space. My thinking is that there is no need for ducting behind the scoop because once it is in the fender cavity it has nowhere to go but through the oil cooler. The path of least resistance and the low pressure area behind the oil cooler is sucking it along.
my 2cents
Jerry