I found this for you,..Der_Meister45 wrote:forgive me for asking what seems to be a simple question with possibly complex answers. But all of the teams seem to be building front wings with out wash from the car, Ferrari and a few other teams add to that with the blown wheel nuts. Is that for that air to wash out completely from the car or for it reattach around the side pods and energize the top of the floor and thus the diffuser?

If I am correct it changes the wake behind the front wheels.