Nitrous Oxide systems can give racers that "extra edge" that may put them in the winners circle. Our own Jack T recorded the fastest 1/4 mile time EVER for a Stealth or 3000GT using a Nitrous system. Handled and installed correctly, they are reasonably safe, but this is one system that we should avoid of, IMO...
This example was a badly-installed Nitrous Express kit (not to be confused with the NoS brand). They wired up the heater directly to 12v (not on a temp switch) and left it on. Then they had TWO pressure release vents on - instead of one - which doubled the emergency release pressure. The car owner claims a malfuntioning safety valve/disc/cap. (?) And below you can see the results.
Fortunately the car was garaged, so no one was hurt. This wasnt a 3S car (it was a modded 91 Nissan Maxima owned by Doyle Schoenberger of Ohio). But these photos bear looking at, just so you know what youre dealing with when you consider adding a shot of Nitrous. This was a professional installation on a spotlessly clean engine, with the bottle kept safely (?) in the trunk!