Just out of curosity wouldn't you lose air pressure when you add a 2nd intake into the air box as the one that scoops the most air would start to push air out the other there for not pressurise as much.

Wouldn't it be better to just increase the original intake snorkel to get more intake pressure.

Well lets not forget that the ability of the engine to suck up all avaliable air would also have to be taken into account. If it is using the air as fast as it is a valiable then the pressure difference arguement would be negated.