my installer does a LOT of nitrous systems for many cars, and he refuses to install zex stuff because it goes bad so often, sometimes catastrophically. i have a nitrous pro flow kit by wilson manifolds, its a great kit. NX, NOS, or NPF are the way to go. zex is garbage. id reccomend a wideband, fuel pressure safety switch, pressure gauge, and bottle heater....and NO MATTER WHAT IT MUST BE TUNED!! if you run nitrous of ANY shot on a motor not tuned for it, you risk it being blown up. i know the s197 3V's can run 125hp shots all the time as long as they have the HT0 plugs, and are properly tuned for it.