FumeFX Implosion

[Jordan]

Im trying to achieve an implosion effect using and am having trouble controlling the look.
I have tried using a negative spherical wind but the velocities go a bit weird and always create a outward velocities in the verticle/horizontal and inward velocities on the diagonals of the grid.
I am trying to get spherical inward velocities.
Any one done this type of effect?