The lower the car goes the quicker it gains camber. I would expect if you are on stock springs it would take aprox 1" reduction in ride height to gain the camber you are looking for. I'm going to guess there is some good reason you are keeping the stock low rate springs. You are going to want to cut both front springs and then reset camber with the upper control arm. Just cutting 1 spring will affect your corner balance. Make sure you cut the coil properly so it will seat in the lower mount.