Quote:
Originally Posted by KRAM36
You have to be kidding me if you think spoilers make a car faster in a straight line. 
They create drag, they press the car to the ground which takes more power to move the car. |
Quite the opposite actually. Instead of creating downforce our spoiler "spoils" lift and often but not always reduces Cd. Airflow lifting several hundred lbs on the tail of the car causes a low pressure zone, turbulence and drag. Solve that and you improve stability, fuel efficiency, and straight line speed. Porsche aerodynamicists understand this, tested and confirmed it. Some grasshoppers not so much.
The modern 991 Turbo takes it a step further with active front and rear spoilers but the goal is the same. Stability, fuel efficiency and straight line speed with the lowest possible Cd.
https://www.youtube.com/watch?v=A9FluxQn0ZE