The enzo uses jabsco ballast puppies to fill, you could T before the pump and run two pumps side by side to double your flow. If you wanted to switch to a high volume bilge style pump it would require reengineering the whole system.
By the way are you getting the 1500lbs side sack from fly high. Check out some of the picks on the inland surfer site. Clean surf wake 20ft back its just amasing. I was out surfing a brand new 06 last night. We had no wieght in it because we were breaking it in and with only 5 dudes the wake was massive. http://www.inlandsurfer.com/album.asp?page=3