(I'm getting the popcorn ready) If you spray a motor too early it causes a LOT of stress on it and you will break it, if you spray nitrous when free revving it its bad for it as well, and you generally want to disable nitrous right before redline(fuel cut) because if you spray nitrous and have a fuel cut you become VERY lean and you will yet again break your car. You may be lucky a few times but it will catch up. Most general pill settings are on the rich side but every motor responds different so like Terry said, its best to get a wideband and tune your fuel pill.