I forgot to mention that vaccum is also a force of lift. Sorry if you mentioned that earlier.... (I guess i really am rusty
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A cup car, NASCAR (Nextel Cup)
Its usually $8k an hour for planes and what not, and cars START at $2k an hour for testing.
As far as the hole, it helps marginally, it relieves the pressure buildup from underneath the radiator as air can only vacate that compartment at a certain rate.
No, I don't think a VG would work on our cars. Its too serious of an angle for it to compensate. Basically, in creating these vortex's it kicks the air down, (the downside of a vortex) in doing so, it re-directs the flow downward. We have too much an area for it to comenspate for. Canards could work but it would take a little to get them dialed in.
I think the biggest help on the fiero (and I am desperately trying to remember the name of this device) is to speed the air up underneath the car. In that sense, the biggest amount of downforce can be obtained.