E46 M3 WMI Design

[mm3boost]

Hey Guys,

I'm about to order an HSF4 WMI setup for my maximum PSI E46 M3. My current specs are:

Precision 6870 turbo / .82 AR
3.5" straight exhaust, no restrictions
3" Intake
ID1050cc injectors
Currently 9 psi low boost pump gas 500 rwhp / 385 tq
High boost is set to 19 psi on MS109 ~730 rwhp

Goals:
With WMI, I would like to be able to run 13-15 psi (550-600 rwhp) on pump gas and 21-24psi (750-800 rwhp) on MS109.
At the moment the plan is not to tune for the WMI, just to add boost and use it as a knock deterrent.



The challenge of this setup is the intake manifold design has a large surge tank and the MAF sensor sits right before the manifold as well. The only position I see that is of value would be direct injection into each throttle body, I've attached a picture of my planned placement.


My main question is that the several of the technical papers I've read on this forum support data that shows the best water/fuel mass ratios to use are between 100-150%, but the Aquamist website claims 10-25% depending on your WM ratio. I'm unsure what injectors to purchase at the moment until I get a better clarification on what the proper ratio to run.



Regards,


~Anthony