By now, a lot of you have your opinions of BMWs new and very controversial kidney grille. Seen in models like the M3 and M4, the front kidney grille is, for better or worse, a visual conversation starter. But as much as it captures our attention, very little has been said about the functions of the kidney grille and, more importantly, what you can find behind the new nose. See, theres more to the kidney grille than meets the eyes, and thanks to Bimmers new M3 and M4 - Explained web series, we get a peek behind the curtain, or, in this case, a peek behind the two kidney grilles.