N2o NOS ZEX NX, what do you think???? Options

[Punch]

NX express, ZEX, NOS has any have some on there car ???? gonna put some on my new motor only a 50 shot...

[NuclearHappineS]

'im talking about the "getting a pro to tune it" part. how the hell do you tune your fuel and timing to accept an instant hit of 50hp out of nowhere? these econo motors are just not strong enough for that type of stress, and the ecu has no clue as to how to compensate for something like that'

how do you tune a motor to accpet some 21 lbs of boost coming in between 3000 and 4000 rpm ?

tuning the motor comes down to 2 things really...tuning the fuel , tuning the ignition timing...

there are other things you can do (tune the cam timing, adjust the 'lobe seperation angle' to maximize nitrous delivery, tune your headers and exhaust for the increased flow, port your head and intake manifold to achieve better n2o distribution if you;'re not going direct port)

but ignoring all that since this is only a 50 shot ...

how do you adjust the fuel ?
the kit takes care of it either by raising your fuel pressure for dry kits or by spraying the extra fuel through wet nozzle....or if you're bad ass you add injector duty cycle through your standalone with a complex dry kit.

how do you adjust your timing?
well nitrous does burn faster than regular oxygen. That's why it requires timing retard. That you you maintain peak cylinder pressure far enough after top dead center to prevent detonation, and to maximize power deliver ... you need 1-2 degrees of retard for every 100 hp added to the motor. given that this is only a 50 shot then you only need 0.5-1 degrees of retard...and given that this is a toyota motor then i'd be damned if toyota put in less than 0.5-1 degree of safety margin in their stock tune...and given that nitrous comes in at some -200 degrees ferenheit then detonation is not really an issue untill you start trying to cram alot of it into the motor ...and given that most kits out of the box are tuned around 10:1 A/F ratio or richer it's very hard for you to even get to the point where you NEED the suggested retard by the manufacturer.

you adjust the timing by backing off your base timing, or by using an msd btm or a crane timing master, or having a different timing map ... or using an apexi ITC and having retard in the higher rpms (say 3000-redline) where you'd be using the nitrous ... or by not retarding the timing at all but always running higher octane or race gas when you spray (which burns slower, hence not requiring timing retard at all)

have you ever heard of a nitrous/methanol kit... it's a wet kit that uses methanol as the supplimentary fuel...methanol is @ 114-117 octane.. you need to ADVANCE your timing to run that kind of a nitrous kit because the octane is so high that the mixture burns slower than the stock mixture...so you advance your timing to bring Peak cylinder pressure back where it needs to be to maximize power delivery...

then there's other things to tune...

some people use nitrous delay boxes or use really short fuel lines to the fuel solenoid and really long lines from the nitrous solonoid ... this softens the 'hit' which really reduces the length of the initial lean spike caused by nitrous flowing faster than the fuel ...

other things to tune are cam timing... advanced exhaust cam timing helps
usually having a seperate fuel pressure regulator on the supplimentary fuel suppline line allows you to fine tune your a/f ratio on the juice without affecting your tune off the nitrous... besides changing jets is more a dramatic change in a/f numbers... whereas adjusting fuel pressure is more gradual...

last but not least ...it is no longer an instant hit of 50 hp... with the newer kits you don't feel it hit anymore...

both the new nitrous oxide system's Noszle (direct port under the injector) kit and their new pro race fogger direct port kits are very soft hitting ... i've seen a dyno of the noszle kit in a mustang magazine spraying a 100 shot and they had the old style dyno output vs rpm

it looks something like this :

3000 +18
3100 +34
3200 +75
3400 +100

so it never really 'hit' ... it gradually came in over 400 rpms... the new nitrous wet kits are the same ...they use the 'soft plume' nozzles that are meant to soften the blow of the nitrous introduction (which is where most damage can occur to the engine) ... and they started going this route mainly because on direct port kits you have little distance between the nozzle and the cylinder so the effects of the activation lean spike could be amplified while the fuel tries to keep up with the nitrous...

year after year nitrous is getting safer and more attractive

-nuke