Bonneville Landspeed Racing - Let's Try a Thing.

There are formulas to figure it out, but from what Chrysler engineering docs say, the stock Charger was approximately 0.44, the Charger 500 in race trim was 0.375 and the Daytona was 0.28. Shutters? For the lower grill opening? The upper is only open as I ran out of sheet metal.

Vehicle aerodynamics
Ya shutters. That's how modern cars work. If the cooling system does not need the air they shutter the radiator so more of the air goes around the car instead of through it. They are also smoothing up the undersides. Eliminating things like rocker pinch welds.