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Old 10-05-2004, 02:48 AM   #1
Handsdown
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Default general nitrous questions, since N/A is closest to n2o

I don't race my car very often and don't want to mod it too heavily, but i was thinking a conservative dry nitrous system might give me the extra power i'd like at the track and still leave my car versatile for daily driving.

i have a 2003 RS, completely stock(ganzflow don't count) with about 20,000 miles(thinking of installing dry nitrous after my 30k mile tune-up with the addition of a higher flowing exhaust system) and i was thinking i could start out with a very modest ~30shot, then take it up to a 50-60 shot once i was sure everything was in order. (injectors doing fine, ECU not retarding timing)

i met one RS owner who ran a very successful dry nitrous system on his car for some number of miles at the northern virginia meet a year or so ago, so i know it can work...

i'd hope to run a zex kit since the throttle-actuated system is of great importance to me, and my friend with a 5.0 mustang highly recommended it.(as well as another friend with a 2nd gen turbo DSM)

i am unsure as to which forum to put this in, because nitrous is not true n/a... mods feel free to move this.

any comments are welcome, but i'm mainly looking for insight as to what to watch out for, what gauges would be useful to make sure the nitrous system is dealing well with the rest of the car, etc. thanks again!
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Old 10-05-2004, 07:43 AM   #2
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Quote:
Originally Posted by Handsdown
any comments are welcome, but i'm mainly looking for insight as to what to watch out for, what gauges would be useful to make sure the nitrous system is dealing well with the rest of the car, etc. thanks again!
An EGT and fuel pressure gauge. If you want to go one step further, an air/fuel ratio gauge and nitrous psi gauge.
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Old 10-05-2004, 07:56 AM   #3
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I've been thinking nitrous would be a good way to go to, and am thinking about maybe doing it. I've heard from people though that if I do go with some N02 then I should run a wet system instead of a dry. I was told it's more reliable than a dry system, but I'm not sure why. If anyone knows which is better and why post up.
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Old 10-05-2004, 08:34 AM   #4
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Default wet

i hear wet is safer.

dan
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Old 10-05-2004, 10:38 AM   #5
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I treat my car like it's my girlfriend...so I say keep it wet.
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Old 10-05-2004, 11:57 AM   #6
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And do you have to change to 91 octane?
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Old 10-05-2004, 12:14 PM   #7
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Quote:
Originally Posted by bahboy20
i hear wet is safer.

dan
you heard right, wet systems are always safer

wet kit takes more nitrous to make the same power because when you run dry you ARE leaning out the mixture due to cylinder temperature drop
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Old 10-05-2004, 12:48 PM   #8
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wet is mainly safer because you're not running the risk of having a sudden drop in fuel pressure while under nitrous spray.

a direct port system is much more costly to install than a dry port system.

i'm going to start saving up with my new job and see just how much i can expect to have for my set up.

and regarding gas... it does need to be premium when you spray, but as long as you are running a fairly conservative shot stock timing and spark should cut the mustard. This information brought to you secondhand via the good people over at the vortex
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Old 10-09-2004, 07:07 PM   #9
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Also, make sure that you use copper sparkplugs of a different heat range and also regap them so they don't get "blown out." I went 1 step colder(if I remember right) on a 50 shot. I use the Zex dry kit on mine, and it works great. I am not sure why it's not as safe as the wet system, because the nitrous "computer" adds the extra fuel that you need through the injectors.
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Old 10-10-2004, 05:36 PM   #10
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just wondering but where can nitrous be injected to?
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Old 10-10-2004, 06:31 PM   #11
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With the dry kit, I would put it about 12" away from the throttle body just securing the nozzle into the intake piping.
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Old 10-10-2004, 09:18 PM   #12
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Quote:
Originally Posted by SpeedbeeqS
With the dry kit, I would put it about 12" away from the throttle body just securing the nozzle into the intake piping.
so it's after the filter? will the nozzle atomize the nitrous enough so that it's fully oxidized the air and not just floating around before it hits your filter?
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Old 10-10-2004, 10:16 PM   #13
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Yes, it's after the filter. The nitrous is atomized fine through the nozzle. Remember that the bottle is pressurized to about 900 psi so you dont have to worry about it "floating around." It won't even touch your filter, it sprays straight into the throttle body.
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Old 10-10-2004, 10:18 PM   #14
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so you drill the intake, or the intake manifold? the plastic, or the metal?

sorry, i just don't know what you mean by after.

i always thought (for dry nitrous)you drilled into the intake manifold, after the air has passed through the throttle body but before it reaches the valves or combustion chambers.

for wet i thought you drilled direct port and it was somehow after the valves...
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Old 10-10-2004, 10:52 PM   #15
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You do not drill into the intake manifold for the dry nitrous system. You drill into the plastic hose before the throttle body. I wish that I had pics that I could show you. What year is your car? I have a '99 so it has MAF, which may be different from your car. That would be why you are getting confused. I am sorry for not thinking about the other years.
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Old 10-10-2004, 10:56 PM   #16
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nah that's alright.

i'm MAP, it's a 2003, and what with my 'tune-up on a budget' autozone approach, i won't be doing any kind of nitrous or hardcore mods for a while.

besides, with nitrous you need cooler plugs and cooler plugs can cause pre-ignition which is not something i want to deal with.
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Old 10-10-2004, 11:09 PM   #17
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Actually, cooler plugs resist pre-ignition more than a hotter plug would. How many miles do you have on it? Do you have a certain spark plug that you like better than others?
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Old 10-10-2004, 11:20 PM   #18
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"Dry" system only adds nitrous at a single fogger (in intake, after air filter)
"Wet" system adds nitrous and fuel at a single fogger (in intake, after air filter)
"Direct port" system adds nitrous and fuel to multiple foggers (one per cylinder in the individual intake runner)

With a dry or a wet system, you put the fogger/nozzle in the intake, after the air filter. Nitrous oxide is a gas at room temperature, and when it depressurizes from it's liquid state at 900psi, it evaporates to a gas instantly, which causes the air around it to loose energy (get colder, pour some alcohol on the back of your hand to see this evaporation/cooling happen). This cooling of the intake charge is one way nitrous works, the other way is simply adding oxygen (the 02 part of N02).

A wet system is safer than a dry system because it eliminates the chance of running too lean by adding extra fuel. A dry system only adds nitrous, and therefore can cause a lean condition. (a direct port system adds both, and has a more even dispersal through each cylinder).

(Pre-ignition is called detonation by everyone else)
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Old 10-11-2004, 12:00 AM   #19
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it has 20k miles on it and i just replaced my spark plugs because the stock ones were misfiring.

i've now had a lot of back-handed help on the boards and now know that the bosch plat's that i put in will be too hot and eventually misfire.

i want some copper NKG plugs, my friend with a DSM recommended the number.

i'm pretty pissed i have to reinstall some different plugs.

it's kinda killed my whole drive for the nitrous thing in ~10k miles though, i'll probably just put in copper plugs and forget about everything but a catback, then get another car when i'm out of college.

also, zex kits add fuel through the nitrous computer(it senses throttle position and actuates both the nitrous and runs a higher pressure through your fuel... i forget the name but the last thing the fuel goes through before it gets to the injectors... the thing after the pump... whatever.)

thanks for the help everyone. i won't be needing it anymore, i'm too pissed at cars now.
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Old 10-11-2004, 12:02 AM   #20
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so your pissed because you need to change spark plugs? good thing your not putting nitrous in your car I guess...
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Old 10-11-2004, 12:10 AM   #21
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Quote:
Originally Posted by tooocool49723
so your pissed because you need to change spark plugs? good thing your not putting nitrous in your car I guess...
i'm pissed that bosch plat's aren't 'good enough' for my engine because subaru only uses copper because of the ecu...

and putting nitrous in my car would be stupid. i have only been to the track once and it really doesn't matter what ET's i run... with nitrous i'd have to get colder plugs, upgraded injectors, gauges up the wahzoo, a better clutch, and a failsafe nitrous system (one that won't lean out) in order to feel safe about spraying. plus premium fuel.

i'd rather just have a slow car.

thanks again for the help... and for your sarcasm and crap that help me come to this cheaper, better solution.

i'm sorry i ever posted.
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Old 10-11-2004, 12:13 AM   #22
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Dont be sorry that you posted, that's how you learn stuff.
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Old 10-11-2004, 10:51 PM   #23
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I dont mean to Hi-Jack this thread but since were on the topic......

Most system's use a WOT switch under the gas pedal to activate the spray(+a safety switch to turn on the system). My question is, does anyone sell somthing that makes it possible to skip spraying in 1st and 2nd gear under WOT? I really dont see a need for it in 1st and 2nd gear as our cars dish out plenty of torque there, also I feel the risk of damaging the trans/clutch would be greater in 1st and 2nd gear on spray.

I thought of a few ways to make it work so I can flip on the switch to turn the system on, and go through 1st & 2nd hitting WOT (with no spray), and then have spray at WOT for 3rd, 4th, and 5th. I would like to avoid using one of my own idea's, and use one that ZEX,NX, or NOS already has(if they do).

Hope this make's sense, I've been up for 24hrs +, and on my last wind.
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Old 10-11-2004, 10:57 PM   #24
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good idea indeed.

my advice- flip the safety switch after you shift into third.


for it to do it automatically you'll have to have one of those things that reads your speed and your RPM and calculates what gear you're in. i don't think any nitrous companies have that... but i wouldn't know
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Old 10-12-2004, 12:21 AM   #25
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There are nitrous computers that can do that, but they cost WAY too much. Your cheapest option (that I know of) would be to put in some switches on the shift linkage, make it so that you have 2 switches, one for first, one for second that interrupts the power to the on switch. Then, when you shift into third, the on switch is on, you hit WOT and spray.
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