ALSO ABOUT ROOF SPOILERS.... IS IT POINTLESS TO ADD A ROOF SPOILER AFTER I ADD A GT WING? BECAUSE THE SPOILER SPOIL THE AIR MOVEMENT RIGHT AT THE END OF THE ROOF PANEL, BY THE TIME IT GET TO THE REAR WING THE AIR MOVEMENT IS DISTURBED OR DIFFUSING AND THE WING WILL NOT BE ABLE TO DO ANY EFFECT? OR SHOULD I MOUNT THE WING HIGHER?

I KNOW I MAY NOT MAKE ANY SCENE OR SOUND STUPID BUT I'M JUST STARTING TO LEARN HOW AERO WORK AND WANT TO MAKE SURE I'M MAKING THE RIGHT CHOICE, SETTING IT UP RIGHT SO THAT IT FUNCTION, NOT JUST SITTING THERE AND LOOK RICEY, ANY INPUT HELPS! I KNOW NICO IS THE RIGHT PLACE TO FIND ANSWER WITH THE HELP WITH ALL SERIOUS MEMBERS, THANKYOU!!!!!!!

And i might be wrong, but it seems to me that the items you are looking at are not functional. Roof spoilers are most often for looks only. The wings, if functional, should have a curved surface almost like an upside down airplane wing.

I don't know what it is that you do with your car or what kind of power you are making that you would need 6 different forms of downforce.

Roof spoilers, such as the Origin style ones are only for asthetics and shade, but can actually interrupt airflow to a functional spoiler. The only functional ones are generally splitters--ie evo or sti. Their function isn't to add downforce, but to smooth air flow to a spoiler. In rallying because the car spends so much time sideways, it helps keep downforce consistent from the rear.

The splitter under the front bumper is supposed to do exactly that. Split the air between under- and over-car. Splitters work most effectively when under car air flow is also controlled. Front downforce is usually determined by bumper design and adjusted with canards.

While you mentioned aero, thought it might be worth mentioning side skirts are only effective with approx. ONE inch of the ground.