Most likely by using that bottle water injection, you will suck air a lot and this alone will lean the mixture, and you will have problem sooner or later.
I have done this, but someone(drex or guan) warning me about damaging valve seal.
Water Injection can be done properly with pump 60-100psi to fog the water coming out of the nozzle.
you can buy the Shurflo pump from herehttp://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_9414_9414
I have buy the pump and solenoid valve, still looking for mist noozle and pressure sensor switch.