nitrous questions

[One_live95]

I think i have made up my mind to spray my car.... i think it would be all the power i want from my car on the spray. So i have started reading, and lets see if i have been productive.

Based on the plugs already in the car, autolite 3924's, i wouldn't need to go another hear range colder would I.

I have a walbro 190 lph that i put in just in case i made up my mind to do this, now that i read about it... Do i have enough pump for a 125 shot?

I am planning on going with the zex kit, i know that may leave a little power on the table but i would rather do that than grenade the motor etc. right now. Does that seem to be the safest kit on the market?

I was thinking i could make around 400hp 450 lb ft withthe spray is this feasible?

Any other imput and general edujumacation is welcome.....lol


thanks guys

[coupe]

ZEX is a great kit. Had a little experience with it on my friend's 347. Went 12.90 on motor. Went 11.77 on the 125-pills. Safe as can be. Easy to hook up too.

Your 190 is enough pump. I would keep the 3924 plugs, but close the gap to around .035. Get an Accell 300+ ignition and coil too if you can swing it. And of course, an AFPR for fuel pressure.
Sounds like a good path to take. Simple. Fast. Reliable. Streetable.

[QWKSNKE]

There is no need to close the gap on a nitrous car. As a matter of fact the wider the gap your ignition will allow you to run, the better.

Good coil and ignition box (MSD, Accel, etc, whatever your preference) and you can run the stock .054 gap or a little higher with some coils. Like Coupe said, the 190 should be enough pump for a 125 shot. You will need to retard your timing 2 degrees for each 25 hp shot OVER a 100 hp shot.

Realistically, unless you are making over 300 to the wheels you will not hit 400 with a ZEX 125 kit. You will make roughly 85-90 rwhp more and 175-200 rwtq more than you make now (whatever that is)

I'll guess 340-350 and 480 torque

[joker]

Personally, I dont care for the zex kits. I am not saying they are bad, but I really dont trust them. The thing I dont like about them is the fact that your nitrous and fuel flow are electronically controlled. The little control box is what regulates fuel and nitrous flow, and determines if the car is at WOT by reading off of the tps sensor. If something goes screwey with the control box, it could lead to something bad very very quickly. That being said, I do not know anyone who has used one of these kits, nor have I heard of anyone having problems with them.

I prefer the old school setups with a mechanical wot switch. If you have the $$$ get a plate kit as well, so you wont have to worry about fuel puddling in the upper intake.

[coupe]

There is no need to close the gap on a nitrous car. As a matter of fact the wider the gap your ignition will allow you to run, the better.

Really? :shrug: Man, the first setup I ever worked on was basically stock GT with a 100-shot wet-kit...damn thing would misfire something awful at WOT (on the jug). Troubleshooting yielded the plug gap. Closed it up and BAM! worked like a charm. :shrug:

[One_live95]

from what i was reading Joker, the dry kits don't seem to have the puddling problem. I probably am wrong though just a thought.


Lee, With the current combo, AFR, Edelbrock Intake, b-cam 1.7's(soon to be custom cam from FTI), 24# Injectors, and everything else in the world that i have thrown at this car, i was hoping for around 300 at the wheels with a little more torque. Oh and i have a msd 6 al, and msd blaster coil, also have the rpm selector switch instead of the pills... Was considering if i don't use the Zex kit, i was gonna put a window switch on the 6al if they are compatible...


About the timing etc, I plan to run a switch chip, would a nitrous only tune keep me from having to retard the timing etc? For the track or a run i could flip it over, and flip it back afterward without having to manually set base timing etc.? Don't know this is why all the questions



jason

[One_live95]

Does the spray add more TQ than HP, i am not neccessarily wanting a certain number, i just want a car that can keep up or not get trampled on by every other car on the road nowadays.

jason

[TheJeanyus]

from what i was reading Joker, the dry kits don't seem to have the puddling problem. I probably am wrong though just a thought.


Lee, With the current combo, AFR, Edelbrock Intake, b-cam 1.7's(soon to be custom cam from FTI), 24# Injectors, and everything else in the world that i have thrown at this car, i was hoping for around 300 at the wheels with a little more torque. Oh and i have a msd 6 al, and msd blaster coil, also have the rpm selector switch instead of the pills... Was considering if i don't use the Zex kit, i was gonna put a window switch on the 6al if they are compatible...


About the timing etc, I plan to run a switch chip, would a nitrous only tune keep me from having to retard the timing etc? For the track or a run i could flip it over, and flip it back afterward without having to manually set base timing etc.? Don't know this is why all the questions



jason
The nitrous tune would include retarded (lol) timing.

[joker]

from what i was reading Joker, the dry kits don't seem to have the puddling problem. I probably am wrong though just a thought.
jason
You are correct sir. I was assuming that you were talking about a wet kit. Not alot of people run dry kits. With a dry kit you dont have to worrry about a wot switch either, because the main point of the wot switch is to keep from puddling in the intake.

[One_live95]

good to hear..........i have been trying to read b4 asking stupid questions...........

thanks so far guys...still wondering about the power levels , and what the system does when you lift your foot from the gas between shifts(if you do)does it shut off and then spray as soon as you hit the gas again... How would it work with a window switch as well, is it still spraying while the revs are coming down between shifts..... didn't really find any info about these things anywhere........





jason

[joker]

good to hear..........i have been trying to read b4 asking stupid questions...........

thanks so far guys...still wondering about the power levels , and what the system does when you lift your foot from the gas between shifts(if you do)does it shut off and then spray as soon as you hit the gas again... How would it work with a window switch as well, is it still spraying while the revs are coming down between shifts..... didn't really find any info about these things anywhere........





jasonA wide open throttle switch will make the nitrous fire ONLY when the gas is all the way to the floor. If a wide open throttle switch is installed, then anytime you lift, the nitrous will stop spraying.The window switch will make it fire only when the engine is within a certain rpm range, or "window" if you will. If you are only using a window switch, and do not have anything performing a wide open throttle switch function then yes, it would still be spraying as long as you were within the rpm range. However, if you had a WOT switch (which in the case of the zex kit is contrlled in thier controll box) then even though you are still within the rpm range , it would not fire because you arent at WOT.
Think of the "safety switches" as a series, and if any one of the switches is shutting the nitrous down, then none will over ride that. Kind of like this (please excuse third grade drawing :jester: ) This is not a literal drawing, but will give you a basic idea.

http://i19.photobucket.com/albums/b189/jokers35th/nitrous.jpg

[Italian LX]

With a dry kit you dont have to worrry about a wot switch either, because the main point of the wot switch is to keep from puddling in the intake.
:shake:

Operating ntrous only at WOT is necessary in any kit!!!! The last thing you want to be doing is shooting 900psi of nitrous into a partially closed throttle. You MUST have a way of cutting off the nitrous supply when not at full throttle!

Some people install a "happy button' in lieu of a WOT switch, but even this shouldn't be pressed unless you are at WOT.

I, personally, would recommend some type of WOT switch (mechanical or electric) in addition to a window switch. Running the juice any other way is asking for big problems. Nitrous hits hard and hits quick and there's not a lot of time for the driver to compensate for mistakes -- the more safety features that will help you out, the better off you'll be.

[Italian LX]

Does the spray add more TQ than HP
YES! The reason is that a nitrous gives a significant horsepower increase right when it comes in at the lower RPM range. More power down low equates to bigger torque numbers. Horsepower is merely a function of torque vs. RPM, so if you're good at math, you can look at this simple equation and see why the low-end high horsepower hit of nitrous gives you the tremendous increase in torque

(Torque x Engine speed) / 5,252 = Horsepower


You can actualy raise your torque numbers at the dyno just by dropping the RPM at which your window switch opens up. You can see this in the two graphs below. Even though you have 50 more HP at 4000rpm, the torque is actually lower.


http://www.deepstageperformance.com/dyno/nitrous-1.jpg



http://www.deepstageperformance.com/dyno/nitrous-2.jpg

[Italian LX]

Personally, I dont care for the zex kits.. .The thing I dont like about them is the fact that your nitrous and fuel flow are electronically controlled. The little control box is what regulates fuel and nitrous flow...
Actually, the ZEX control box DOES NOT regulate nitrous -- that's what the jets are for. The ZEX box only regulates fuel and it is based off of what nitrous pressure it is obsrving from the bottle. This is actually a good idea and removes some of the hassle about worrying where your nitrous pressure is during a run. This works in both the wet and dry configurations.

. . . and determines if the car is at WOT by reading off of the tps sensor. If something goes screwey with the control box, it could lead to something bad very very quickly.
There is just as much risk in any nitrous set-up.

A mechanical WOT switch could fail due to a faulty spring mechanism not allowing it to open back up or something could get wedged against it. Using a TPS sensor is not a bad way of determining the WOT state. A failing TPS sensor will normally read 'open' or low and will just render your nitrous system useless.

As far as the control box possibly leading to problems.... there are equal risks in any variation of nitrous set-ups. Any said nitrous solenoid could stick open or any fuel solenoid could fail to hit (whether it be due to a wire break or a faulty solenoid) and either would probably cause major damage before you realized it.

[Italian LX]

Jason (One_live95),

I'm not trying to scare you with all of this; I just want to clear up any misconceptions that some people may have about these kits.

As long as your wiring is top-notch, you use good quality components, and incorporate the proper safety equipment, you should have very few problems.

[Italian LX]

Based on the plugs already in the car, autolite 3924's. . .
What heads are you planning on running?

[TheJeanyus]

I would word it the other way around, that nitrous gives you a huge increase in low end torque, thus increasing low end horsepower and as a result the "area under the curve" of the horsepower graph across the entire RPM band, but that's basically just another way of saying the same thing Brian said.

[LeeH]

:shake:

Operating ntrous only at WOT is necessary in any kit!!!! The last thing you want to be doing is shooting 900psi of nitrous into a partially closed throttle. You MUST have a way of cutting off the nitrous supply when not at full throttle!

Some people install a "happy button' in lieu of a WOT switch, but even this shouldn't be pressed unless you are at WOT.

I, personally, would recommend some type of WOT switch (mechanical or electric) in addition to a window switch. Running the juice any other way is asking for big problems. Nitrous hits hard and hits quick and there's not a lot of time for the driver to compensate for mistakes -- the more safety features that will help you out, the better off you'll be.

You are 110% correct sir.
I have always wired in a relay with a fuel pressure safety, oil pressure and clutch switch tied in to interupt the ground circuit on the - side of the coil in the relay, Then have a master on/off switch to supply the power to the + side of the coil and a second relay wired through the WOT switch to supply power to pin 30 of the relay. There are many ways to wire in safetys to help prevent the chance of an accident.
A dry system can still experience a backfire in the intake. There are a few ways to install a dry shot, I like to shoot through the MAF with small shots. There are numerous reasons to have a nitrous backfire but look to a lean missfire as the root cause. This can be from activating at too low engine speed or a bad tune. See it takes 572*F for the release of the bonded oxygen molecules, Intake air temp will drop while your spraying because when nitrous leaves the nozzle or spray bar its roughly -127*F. This extreme low temp will drop the intake manifold air temp about 70*F so with this info please understand its usually missuse or mechanical failure that leads to a backfire and not the type system used.

[joker]

:shake:

Operating ntrous only at WOT is necessary in any kit!!!! The last thing you want to be doing is shooting 900psi of nitrous into a partially closed throttle. You MUST have a way of cutting off the nitrous supply when not at full throttle!
Hum, Blake at the dyno is the first person I heard that from, but I guess he doesnt know what he is talking about :shrug: I have also seen it done and done it on multiple occasions without any reprocussions, but I guess we were very lucky not to scatter the engine. Thanks for the heads up though.

[One_live95]

What heads are you planning on running? I have already bought and installed a set of AFR 165's. planning on keeping them a while....

[joker]

Actually, the ZEX control box DOES NOT regulate nitrous -- that's what the jets are for. The ZEX box only regulates fuel and it is based off of what nitrous pressure it is obsrving from the bottle. This is actually a good idea and removes some of the hassle about worrying where your nitrous pressure is during a run. This works in both the wet and dry configurations.I still dont go for it, instead of the pills adding the right amount of fuel, you are relying on the control box and the pressure signal from the bottle, just seems like it over complicates things to me more than anything.




A mechanical WOT switch could fail due to a faulty spring mechanism not allowing it to open back up or something could get wedged against it. Using a TPS sensor is not a bad way of determining the WOT state. A failing TPS sensor will normally read 'open' or low and will just render your nitrous system useless.

As far as the control box possibly leading to problems.... there are equal risks in any variation of nitrous set-ups. Any said nitrous solenoid could stick open or any fuel solenoid could fail to hit (whether it be due to a wire break or a faulty solenoid) and either would probably cause major damage before you realized it.
Yes, like I stated, I am not saying they are bad kits, I just prefer the standard kits.

[One_live95]

Jason (One_live95),

I'm not trying to scare you with all of this; I just want to clear up any misconceptions that some people may have about these kits.

As long as your wiring is top-notch, you use good quality components, and incorporate the proper safety equipment, you should have very few problems.


In lieu of everything you said, i would think that I will be ok with all the safety precautions that they put in the ZEX kit.... They seem to have a WOT switch based off the TPS... I think ican slip the clutch off the line and then go WOT, but then again i have never driven a car off the line like that.

I am meticulous about wiring etc. so i should be ok there..... and probably will bug you guys here if/should/when problems come up on any install.....lol

BTW... thanks Brian, i knew you would stick you nose in here sooner or later:chug: lol and BTW.... how do you like your car on the "JUG" ?

[One_live95]

You are 110% correct sir.
I have always wired in a relay with a fuel pressure safety, oil pressure and clutch switch tied in to interupt the ground circuit on the - side of the coil in the relay, Then have a master on/off switch to supply the power to the + side of the coil and a second relay wired through the WOT switch to supply power to pin 30 of the relay. There are many ways to wire in safetys to help prevent the chance of an accident.
A dry system can still experience a backfire in the intake. There are a few ways to install a dry shot, I like to shoot through the MAF with small shots. There are numerous reasons to have a nitrous backfire but look to a lean missfire as the root cause. This can be from activating at too low engine speed or a bad tune. See it takes 572*F for the release of the bonded oxygen molecules, Intake air temp will drop while your spraying because when nitrous leaves the nozzle or spray bar its roughly -127*F. This extreme low temp will drop the intake manifold air temp about 70*F so with this info please understand its usually missuse or mechanical failure that leads to a backfire and not the type system used.


i can assure you guys it will have a tune that is stepped up in increments b4 it gets sprayed....lol Thats interesting info on the temps etc., would you say that a wet and dry system are equally safe?

[QWKSNKE]

I forgot you had the AFR heads Jason. Sounds like you almost have the same setup as I had in the 93 a few years ago. Check out the Cobra thread in the dyno room ;)

I am kinda like joker. I don't care for the ZEX setups. I prefer the WOT switch and rpm window switch. Also, I do not care for the dry kits whatsoever. They tend to overtax your injectors because of the massive pressure your fuel goes up to. Fuel puddling with a wet kit is only going to happen when you are running a massive shot (like 200). I ran my NX kit at 100-150hp for 4 years and never had a fuel puddling issue.

Coupe, with aftermarket ignition you should not have to close up the gap like you do with a FI car. With a scremon demon coil, MSD 6a, I ran my plugs at .060 gap. Never had a problem.

[One_live95]

i am open to suggestions on the kit.... simplistic is fine with me......just want something thats not gonna give me fits..... Based on the combo you had prev. on the cobra, i can over 400/500 with a 150 shot....... I looked in the thread and didn't see what kind of track times you got out of those numbers. I am going to assume thats enough to put my tank deep in the twelves?

jason

[EZ SPEED]

I used a Zex kit for a very short period of time and never had a problem with it. I also know a guy that used a Zex kit for years and it was very reliable.

I also perfer a "wet" kit, but that is a personal preference based on my research.

I have also had some experiance with the Nitrous Express kits and I like those also.

Just thought that you might want to hear another opinion ...or two ;)

[QWKSNKE]

i am open to suggestions on the kit.... simplistic is fine with me......just want something thats not gonna give me fits..... Based on the combo you had prev. on the cobra, i can over 400/500 with a 150 shot....... I looked in the thread and didn't see what kind of track times you got out of those numbers. I am going to assume thats enough to put my tank deep in the twelves?

jason

I ran 12's with a 100 shot and stock heads with drag radials :D

best time with 150 shot, AFR heads, etc was 11.57@118 on 8" et drags.


Oh yeah. NX kit all the way :metal: Just look at the NX solenoids compared to others and you will see a big difference

[Wickd GT]

Anything over 150 you would need to use a 3923 plug. If you are going to use nitrous, depending on the compression and shot you are going to use, you close the gap on the plugs. If you have a plug that is gapped at 0.054, you close it to about 0.040, if you are going to spray 200 shot, you gap it at around .035". If the gap is to wide the nitrous will try to put the spark out making it miss fire which takes the crown of the piston and lips it up. Make shure you have a retard box too, unless the Zex kit has one in the box.


Edgar

[One_live95]

i know i won't go over a 150.... I will start looking around at the NX Wet kits.... seems to be the concensus, I am just kinda getting a little power hungry here lately..... I did take a stroll against a 350Z yesterday though.....lol

11's with a 150 would be all i want i think....I don't see myself wanting the car any faster than that...................................til its sees boost...lol


jason

[Italian LX]

Hum, Blake at the dyno is the first person I heard that from, but I guess he doesnt know what he is talking about :shrug: I have also seen it done and done it on multiple occasions without any reprocussions, but I guess we were very lucky not to scatter the engine. Thanks for the heads up though.
I'm sure you misunderstood what he was saying. Next time you see Blake, ask him if he would shoot nitrous while only cracking the throttle at 25%.

I tell you what.... when you get your coupe running, install a dry kit on it and we'll do some part-throttle nitrous tests. If is doesn't make any fireworks or ruin the motor, I'll pay for the nitrous kit. ;)

[Italian LX]

I still dont go for it, instead of the pills adding the right amount of fuel, you are relying on the control box and the pressure signal from the bottle, just seems like it over complicates things to me more than anything.
That's like saying that a mass-air system complicates EFI controls. Sure, a speed density system may be capable of slightly higher power gain, but it makes tuning more essential and also leaves out the ability to fully change with variable external changes.

The function of the ZEX box may be more complicating, but it simplifies what the driver needs to worry about. You have less worries about having ample nitrous pressure in order to get a good fuel/nitrous ratio.


On a side note, I too would rather a NX wet kit all the way. I'm only explaining about the ZEX kit for Jason since he mentioned it.

[coupe]

BTW...the ZEX kit DOES use pills. :yup:

It's basically a control-box with variable solenoids inside it...as opposed to on/off solenoids. It reads bottle-pressure, like brian said, and compensates somehow...

The ZEX kit is dead-reliable, safe, and easy to hook up.
Like I said: Dry kit on that 347 went from 12.90 to 11.77 with the arming of a switch. I almost bought that kit.

[LeeH]

i can assure you guys it will have a tune that is stepped up in increments b4 it gets sprayed....lol Thats interesting info on the temps etc., would you say that a wet and dry system are equally safe?


Yes both are equally safe, I do like wet kits better but thats because they are far more versitile and I have way more experience with them. My current dry system will be changed over to a wet as soon as I can afford to swap out the solenoids and buy a plate for my intake.
As far as the argument over WOT activation its a safety practice to help insure against damage or injury, Just make sure the engine is under a load and above 3k rpm. I like to pull 1* total timing for every 50HP to about 200HP then above that it changes again, For anything above 200HP I have found 3* per hundred to work best for me.

NX solenoids will flow more than any of their competitors out there!!! NOS kits are tried and true but wont provide the ease of installation the ZEX kit offers. Once you learn about these manufacturers/kits and understand them better you will find that building one is usually the best way, The NX stuff will offer more flexibility for future expansion and reliabiltiy is excellent with both NX and NOS.

[One_live95]

i was looking at a NX kit on summit..... i found one that was a beginner kit or whatever says 50-75 shot..... comes with solenoids, bottle etc.... would you be able just to add jets to it later and get like a 125, and 150 shot out of it...



jason

[QWKSNKE]

i was looking at a NX kit on summit..... i found one that was a beginner kit or whatever says 50-75 shot..... comes with solenoids, bottle etc.... would you be able just to add jets to it later and get like a 125, and 150 shot out of it...



jason


Is it a different price than the EFI 50-150 kit

[One_live95]

yeah its like 350$ versus around 550...... i know this isn't a place to skimp though, so disregard my previous question..



jason

[coupe]

Take a good look at the ZEX again. It's super easy and it looks great.

[One_live95]

i am still looking......haven't made a final decision yet..... I actually kinda heard of a local guy that has pretty much a brand new kit he might get rid of .....



jason

[onebad12]

Jason I am from Dothan also. I went with a Edelbrock kit, I have seen were alota guys have switched from NOS to Edelbrock kits and really like them, including a friend of mine from Enterprise that races ProMod's. Of course mine is carbed and not FI anymore. What head gaskets did you use with your AFR's? I have AFR 185's on mine.

[One_live95]

i used the 1011-2's for easy clean up in case of a mishap..... Where in dothan are you from, maybe a little get together with us dothan guys would be a cool thing..\

i will look into the edelbrock kits as well... thanks :nice:

jason

[onebad12]

I live off of Fortner street, Chestnut Ridge. I have almost got my car running, still have to finish the plumbing under the hood and wire the ignition.

[One_live95]

have to get up with ya one day... :nice:


jason

[udloose]

One_live95,
the old stock 302 I had in my car, I ran 250hp worth of NOS on it, All I done was put in a set of autolite 23s' gapped at .035, and pulled out 10 degrees of timing, and spray the hell out of it, the car ran 13.30s@100mph on the motor, and 11.73@120 on the spray....no need for alot of other stuff as long as the AFR is at about 12.5:1 or lower.....

[One_live95]

sounds like a mover......lol

i will not spray near that much on it...lol but good to kow you can..... also what year car was that, as some of the older cars had forged pistons.


jason

[udloose]

yeah, it was a 1989 motor, it had forged pistons....

I actually stepped the NOS up to a 2 stage, 250hp on the first stage and 125hp on the second stage, IT RAN LIKE HELL, until you shifted into 3rd gear, then it had a lean backfire through the intake, and fell on its face, it ran 105mph in the 8th, on both stages...NEVER DID TEAR IT UP THOUGH...