Comment by mrandish
1 day ago
At race speeds (say over ~150 mph), you don't even need a fan or any active mechanism. Just passive venturi channels on the underside can generate so much down force they are strictly limited in F1 because they can easily enable cars to sustain extremely unsafe speeds.
There are some McLaren street cars that use passive venturi channels which from their shape alone, generate more down force at high speeds than the car's weight. In theory, the car could drive upside down (if there was a Daytona-sized race track shaped like a ~30 ft diameter pipe).
Even though average lap speeds in F1 can be around 150 MPH or faster at some tracks, corner speeds are generally much slower (in some cases approaching relatively pedestrian city speeds). The beauty of active suction is it allows for much higher corner speeds on the slow sections of the track where traditional wings and underbody elements produce relatively little downforce (being proportional to the square of the car’s speed).
An F1 car would need to move at over ~100 mph to sustain inverted driving (assuming you modified the ancillary systems appropriately—the road orientation isn’t the only limitation); a fan car can do it standing still.