You'll get a bigger hp increase just by turning the AC off.
Over the years there have been all kinds of gizmos: "ram air" funnels, electric fans, ice-cube holder air cleaners, mist injectors etc., etc., etc. that claimed a supercharging or air cooling effect effect. For a street car, you need 5 to at least 10 pounds-per-square inch air pressure into a sealed system to gain significant horsepower - your AC isn't gonna do it.