[MetroMPG]

Just noticed something:

2.3% = gain from outside mirror changes
2.3% =gain from partial boat tail prototype
2.2% =gain from undertray

Edit: also tested

2.8% =gain from wheel skirts*
2.9% =gain from grille block*

* winter testing - denser air - also I tested at 95 km/h, whereas the ones above were between 88-90 km/h.