So after using my beloved calculator, I have established that a racecar, lets just say it's a stock car, travelling at 60m/s or whatever Grvliploloolpoop said the speed was, would exert about 248Pa of pressure. Where as a, lets say, 5mm exerts maybe 65kPa of pressure. That doesn't help ANYONE who doesn't know metric ;) besides, It's probably WAYYYY off.