Most water injection systems utilize a 150psi or so pump to atomize the water. Gasoline will atomize much more readily, hence the lower pressure. No water injection system is recommended pre turbo. I know from experience that Holley pumps will not pump water for very long at all before they won't work due to corrosion of internal parts.

"The first rule of overkill: You can never have too much overkill."
"Overkill is underrated."