[cfd_guy]

Originally Posted by kach22i

2. The Most Important are the Aerodynamic Changes on the Under-body of the Vehicle!
6 TIPS Why Better Aerodynamics provides Better Fuel Economy!

This picture exert from one of my aero books shows areas to target with biggest benefit for underbody of vehicles.

Originally Posted by kach22i

5. It is All about Coefficient of Drag!
6 TIPS Why Better Aerodynamics provides Better Fuel Economy!

I think CdA is better than just Cd to use personally. If you increase the area while decreasing the Cd might not gain you anything mpg wise.