Sam details for us a water injection setup on his MK-III with Neuspeed Supercharger. His is set to engage at 6 PSI and he says there you can definitely feel a push when it comes online.
Link: http://c3cars.com/CFJFiles/C3Cars/7895.wmv
J.Schecter
Link: http://c3cars.com/CFJFiles/C3Cars/7895.wmv
J.Schecter