As long as you use it correctly, NOS will not hurt your engine. From what everyone has told me, a dry kit is the safest way to go. As long as there is enough fuel being delivered, you will be ok. I have been told that you shouldn't push your pistons to hard considering they are not forged but a 75-100 shot will be ok. One thing to consider, you are going to want all the extras for it(gauges, timing control, remote bottle valve, purge kit) they will make things safer and more convienent for you. I started out thinking it will cost me 450 for the stage one and thats it...well, went with stage two and goodies that put me at about 1000 bucks...It is WELL worth it though, Cant believe how much power she is puttin out now!
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My Mustang
91 LX Conv. 52,000 orig mi. Hurst shifter, 3.55 grs, NOS 150 dry kit, MSD 6al, MSD timing control, malory coil, pullies, fms adj fuel reg, BBK 70mm tb, Pro-m 75mm maf, battery in trunk, JBA shorties, JBA subs, JBA strut tower brc, dynomax "super turbo" 2 1/2 exhaust, FMS billit distrib, Hotchkis lower cntrl arms, MAC Fenderwell cold air kit, off road h pipe.