Don Most cars have ram air already?
No, most manufactures have done everything to make inlet ducts to get air into the engine. The problem is that because of the path the air has to take, by the time it gets to your throttle body, the air doesn’t have enough pressure and speed to add any ram pressure to your intake system. Even at speeds of 80 mph, no ram effects can be measured with an almost perfect inlet system (i.e. less than .08psi). At 160 mph , that pressure goes up to .36psi., that’s it!! Horsepower robbing vacuum in most air boxes is present due all sorts of restrictions as we cant have dragster style hood scoops on street cars because we would not be able to see over them!