musclemustangcb, the V1 actually flows more than the V2 and can spin faster.
Some companies do port jobs on the inlet side and install impellers with more of an angle or curve to the blades. They say you can gain about 1-2 lbs of boost without swapping a pulley. You can also use an Anderson Powerpipe, that will give you about 1-2 lbs of boost without a pulley swap.