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i was just wondering why everybody says they are not as good or are more dangerous than wet systems im gonna get a dry zex kit for the ease of installation but am wondering why its so bad and if it really is that bad i might go with a wet kit thanx

a dry shot is just that...all nitrous, no gas. lets say #1 injector fails. now all you have in #1 cyl is nitrous and no gas. this plus compression+air+spark=bad. with a wet system, you'll always have some gas in there to help "burn" the mixture properly.<p>i'm not into nitrous all that much, so i'm sure others can add some better input.

A lot of has to do with safty margins.. you need to know how much fuel you stock injectors can dump into the motor and stay under that limit. Nitrous is a means of inducting oxygen, dry systems augment the fuel pressure to make the injectors shell out more and try to account for the increase in oxygen in the combustion chamber.. Aka its the ghetto rigged way..<p>Wet systems inject both nitrous and fuel, which allows safer tuning as of there is no guess work or praying that enough fuel gets dumped in.

I use a Zex dry system. The Zex dry system is about as safe as it gets, as far as dry kits go, because it runs on vacuum from the fpr and bottle pressure. A vacuum hose gets connected to the Nitrous management unit from the fuel pressure regulator. The unit reads the bottle pressure to automatically increase the fuel pressure. No fuel pressure = no nitrous. If the the fuel pressure is not within the bottle pressures ratio parameters it will not engage. If the fuel pressure ratio is below bottle pressure the NMU will ease off the nitrous and vise versa. As a result regardless of bottle pressure and fuel pressure the amount of fuel to N2O is always consistant. if the fuel pressure is too high the excess bleeds off through a line back into the IM. The only time you really have to worry about lack of fuel with this kit is if your engine is heavily modified. (turbo/supercharged, ported, head work etc)in which case you'll have to upgrade the fuel pump and possibly injectors. But for mildly upgraded cars with minor mods like intake and exhaust it will work safely right out of the box. As for installation, unlike some other nitrous systems where you have to fabricate a bracket to the throttle linkage for activation of a switch, which means if I'm in WOT the N2O would be injected no matter what. This one gets wired into the TPS voltage out. when you program the NMU it learns the throttle voltage curve (4.2 to 4.5v if I'm not mistaken) and will only fire within that parameter and not just because I hit WOT. Great protection if there is a short or bad contact in my wiring somewhere. (which incidently there is but that's another thread) 3 wires, power, ground, TPS. Like any Nitrous kit however,(wet or dry) it's only as safe as your vehicle is properly tuned.
So ..there you have it. Not everyone bad mouths dry nitrous systems. It would be better to bad mouth just the BAD dry nitrous systems. This one is great.
www.zex.com<p>[ July 17, 2003: Message edited by: Darren Hyderman ]</p>

thanx darren i think i am gonna go with zex after all

and so you are aware......the TPS wire you hook up to the NMU is the 2nd from the top.<p>And the bigger the shot of N2O you go the more you have to retard the timing in order to prevent detonation. in 2 degree intervals....55hp 0degrees, 65hp -2degrees, 75hp -4degrees etc.
Lemme know if you get it and how you like it.<p>[ August 01, 2003: Message edited by: Darren Hyderman ]</p>