What orfice size? "HP shot" as a way to measure what your spraying is useless.
You dont have to worry about it being a liquid at low RPM....you have to worry about it knocking the fire outa the motor.
Untill you have a built trans and are running low 13's N2O is a waste. When you also start running big power with drugs you also hav to consider your motor on barrowed time.
Now......how much is too much? I ran in the low .04 orfice first stage and mid .08 second stage and didnt have issues.....your results may vary though and I'm sure my rods were shorter than stock