Lift and down force

Vehicle aerodynamics can also change the weight of the moving vehicle
Downforce pushes wheels more tightly to the ground.  That is desirable.

Spoilers increases downforce.


Downforce is a good thing for cars. Is it desireable for a Gravity car or a CO -2 Draghster??

Lift increases with speed.


While not a good characteristic in car design, lift will reduce the friction tires create on the ground. This would be desirable for a Gravity car or a CO- 2 dragster...