*Blocking your grille has proven to be effective - just remember that your radiator (and grille opening) were designed for the worst case cooling scenario. So monitor your engine temps and adjust your grille opening accordingly.
- Fold your mirrors. If you can, fold your rear view mirrors in. Just be sure to stay in compliance with local laws.
- Belly Pan - A significant amount of resistance comes from the open areas under your car. Covering them with corroplast or some other material can reduce your drag coefficient (Cd)
- Wheel skirts - covering your wheel wells to keep your cars body one contiguous object can help
- Air Dam - see image, if you car doesn't have one already, this can help
- Always Drive with your windows up