Hi

Many factors involved, the kits as supplied are set very rich for safety reasons to stop the ' boy racer brigade blowing up their engines.

Jet Horsepower is @ 870psi higher pressure will produce more Power. Pressure drops after a few seconds on the throttle so keeping Big Power on a Topspeed run requires a Hydrogen push system like mine to keep pressure at 1000psi all the time. Smaller systems are single Fogger which is a bit hit & miss. Big Power will require direct port for more accurate spraying of the Nitrous.
If you are going for Max Power from a system the Nitrous will require to be mapped & Controlled by your ecu, mines done before each run.

We checked on a R-R & were getting 90% of jet Power but we didnt check at what pressure so of very little use.

Chip is the real expert on here im just good at picking his brains. Have run Nitrous for over 3 years with no probs so if fitted correctly it dont destroy your engine.
Cheers Rod