aero or not??? (OEM rear wheel arch 'flaps' - Fiesta, Megane, Clio)

[NickelB NL]

I.m noticing these "flaps" more and more on mostly ford fiestas. Renault magane's and renault clio's. Both molded in the bumber and as addon. Can someone explain how it would work. In my mind it is to direct the wheel turbulance.

[Eddie25]

its regulation in some countries to have a certain % of a tyre covered by a bumper or wheel arch. nothing to do with aero. I also thaught the same until I saw this article.
see below
Ford Fiesta : Test Drive & Review - Team-BHP

What is this mysterious little flap? It was an add-on so the car could meet homologation requirements in certain countries that require a certain percentage of the wheel to be covered by the wheel arch.

[NickelB NL]

Ok. Sounds plausible. But why are there the same model cars without those things.

[freebeard]

Regulations are different in South Sneek?