AFR and Meth Injection?

[NoDestiny]

I have been researching water/meth injection the last week or so, trying to make sure I have a very good understanding before I order and install.

Couple simple questions I have...
-With 11-11.5:1 being a good target and 12-12.5:1 being the leanest you want to get into on your average turbo car using regular unlead gasoline, should one go richer, leaner, or stay the same with a 50/50 water/meth injection?
-(similar question) How much does the water/meth injection change AFR? What is safe, since Stoich for meth is obviously not 14.7:1 as gasoline is, as I find it at 6.4:1?
-Will the water/meth injection actually be seen on my wideband AFR meter?

Obviously there are ALWAYS variables, but is there any general rule of thumbs for any of this? Possibly more accurate calculators out there?

[ShelbyMopar89]

I installed the devils own kit on mine. I am running the innovate XD-16 and there are time where it seems to richen it a bit and times when it does not seem to do anything. I am still tuning and have not got my A/F where I want it yet. I am running my fuel pressure as low as I can go without starting issues and at 23-25 lbs (boost) I still see mid to high 10's A/F wise. In effort to get it into the 11's I turned the injection off, thats whats kinds weird sometime it will make a diff and sometimes it won't. I do not know if it is other variables that change it or what. I am running wiper fluid with the smallest nozzel. Maybe I need to go up one on the nozzel? Still trying to figure it out, not sure if this helps but at least it is something.