I did some more research after I had posted about the fans sucking the car to the ground. I know this would not work in this format for FE, these race cars were using over 20hp to drive these motors/fans.
Here is another option though to get free Horsepower to drive a pump like I am suggesting. I know this may sound crazy so I we need someone to tell me this just to confirm that I am indeed crazy, mounting a turbo on the engine that would not put a single CFM into the engine, it would just put air out the back of the car? Some of the turbos out there put out over 750CFM, if there is no waste gate on this turbo and it developed say 30psi of boost, that is 750CFM going out the back of the car in the dead air zone, I think that it would smooth out the back aero of the car. The added bonus of this would would be the amazing whine the turbo would make going down the road.