Hi, if you're going to have variable pitch rotors, ie. normal nitro helicopter rotors?, then why have 4? the whole idea (as far as I understand it) of the 4 rotor system is to avoid the need for the mechanical complexities of variable pitch, so you only need to vary the relative speeds of the rotors for control.
This isn't to critisise, I'm just interested why you would go this particular route?
good luck with it anyway