NACA ducts on bonnet

[Michael Fling]

I have been watching GT races at Brands Hatch (Mercedes, Lambo, Ferrari, McClaren, Audi, etc,). Many of the cars have NACA ducts on the front bonnet oriented for "air in" not out. They don't appear to be positioned for brake ducts. Any idea what they are for?

 

[Doug S.]

Cockpit ventilation??