Does a spoiler on a front wheel drive car do anything? Why would a FWD vehicle have a rear wing? There are many reasons a spoiler or rear wing can be beneficial, regardless of which tires are driven. A car with a proper rear wing will be able to corner faster, brake faster, and can have reduced lift.
Spoiler vs Rear Wing - http://youtu.be/DYpxcE7rBw8
Traction Circle - https://youtu.be/JjCcFsGLpaM
Downforce - https://youtu.be/c9BgfCbZTLM
Aerodynamic Drag - http://youtu.be/eWTsXrPWl5Q
Cornering Speed - https://youtu.be/fjrOsp6S8rA
Center Of Pressure - https://youtu.be/eH63QwQnD0w
Braking Distance - https://youtu.be/Vx4Gigi8uL8