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For those wanting to ask questions about nitrous kits and those who would like to contribute their experiences here is your thread!

One question I have been asked a fair bit;

Question:

I have a GTST and was wondering if I need to change/re-map the factory ecu to fit a nitrous kit.

Answer:

No you don't need aftermarket management, it's always nice to have since you can tune the ignition and fuel maps for better non-nitrous base power and fine tune your ignition map for the nitrous activation but, it's not necessary for kits that add under 200hp. I had a GTST for example with what some might consider a rather large shot and a factory ecu. Having said that I also ran (as one always should) a big fuel pump to allow for the additional fuel requirements of the nitrous kit. A larger fuel pump may upset the fuel maps a tiny bit however I did not find this to be the case when I used mine.

I should add that base timing needs to be retarded a few degrees but, this can be done via a CAS adjustment using a timing gun. If you have a Power FC or something similar it's easy-peasy to do the adjustment without leaving the drivers seat, again you don't need an aftermarket ecu but, they are nice aren't they :)

Next....?

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Strutto,

I had a NOS brand Fogger nozzle (2rismo will know which one because I have forgotten) plumbed in just before the throttle butterfly underneath the alloy pipe that goes over the spark plugs (in fact probably just above the pugs). The solenoids were mounted right onto it . Consequently I did not use the spark plug cover the RB25det normally has to accomodate. The solenoids were mounted hard up against the fogger so as to minimise the lag time between the activation and effect and also the shut down time. This is the time taken for the fuel and nitrous to travel to the nozzle and then for the remaining nitrous and fuel between the nozzle and solenoids to be consumed. My nozzle was so situated and hidden to avoid unwanted attention it need not be mounted that way.

This setup meant that I could full throttle a little closer to the normal power redline without the usual "off the throttle but- it still keeps reving" senario that usually scares the poo out of you the first time it happens. Worse is the direct port setup for this if you don't get the lines short enough.

oops I went on a bit there...

The jet sizes .

I'll have to check what I ended up (fuel and nitrous) with before I sold the kit to 2rismo.

Conservatively I'd say it was about 140rwhp worth, based both on the sizes and the consumption of gas. Sizing the jets is critical. All I can say is the chart for jets is only a 'GUIDE', I think NOS is good enough to point this out on it's pages. One very big factor is fuel pressure. From memory and someone can check the charts for EFI most often take 40psi of fuel pressure as a given for the jet matches, for use in perhaps a NA EFI motor. This is not assuming a rising rate situation, so unless you set a static fuel pressure for a dedicated line of 40psi you can safely assume the sizes are completely wrong. You have to know what the fuel pressure is when you are at full boost as a starting point then test the jets flow per minute at that pressure to make a guesstimate of the right size to use. The other big factor is the brass 'flared' jets used by NOS being a little inaccurate. This is why they have a 'saphire' range that cost a bomb for the sake of accuracy. I dont have jewlers equipment/measures so I tend to lean towards flow testing, doesn't take too long.

michael,

What are you wanting to do? The duel stage kits look to me like more pain tuning than the benifit. Traction is easy to control it's your right foot. If you don't plant it to the floor the micro switch doesn't activate the kit and you don't go sideways (as much), that's my veiw.

the shot is best plugged in once you have a few rpm on the board and are at least moving forward. In the first place letting it all happen a very low rpms is asking for bent rods due to the massive torque plus it just makes burnouts that much easier.

rev210 - going off the NOS guide, you had a rich-ish 120hp setup.

Incidentally, I just bought a dozen or so new jets and now have the correct setup installed (as of 30 mins ago) for 125hp. It's mental..... I mean.... off to the dyno!

Adrian

michael,

What are you wanting to do? The duel stage kits look to me like more pain tuning than the benifit. Traction is easy to control it's your right foot. If you don't plant it to the floor the micro switch doesn't activate the kit and you don't go sideways (as much), that's my veiw.

the shot is best plugged in once you have  a few rpm on the board and are at least moving forward. In the first place letting it all happen a very low rpms is asking for bent rods due to the massive torque plus it just makes burnouts that much easier.

rev210, im looking to boost my overall hp by about 100 or so (i am currently making around 212rwhp @ 12psi, so adding a 100 or alittle less should be give me around 300rwhp correct)

I will mainly uses it for drag racing, (would like to hit a low 13, maybe high 12 with the nitrious)

Im not sure about the NX brand, but i belived that is the kit my friend can get from indo, or should i just look for a system like nos which has been uses in other skylines before?

EVL_33: With only 212rwhp (158rwkw) im guessing you have just a cat-back exhaust and a pod filter or something?

Rev210, im guessing it would be advisable to do the usual fmic, fuel pump etc (so basically a 180-200rwkw GTS-t) before adding the nitrous or would EVL be fine adding it right now?

I will mainly uses it for drag racing, (would like to hit a low 13, maybe high 12 with the nitrious)

You wont need much more than better tyres and practice to run low 13's mate. Go the gas anyway but just make sure you don't get too far ahead of your ability or you'll go backwards.

Adrian

You wont need much more than better tyres and practice to run low 13's mate.  Go the gas anyway but just make sure you don't get too far ahead of your ability or you'll go backwards.

Adrian

thanks for the replys :)

My car has the following mods

VG20 turbo (this is the reason for only 212rwhp @ 12psi)

FMIC

Tomei 550ps Fuel Pump

Airfilter

exhuast (is still running stock dump)

bov

also have 235 tyres all around and d2 coil-overs

The reason for the nitrous was that my turbo is small than stock rb25 and for the same cost of the stock trubo i can pick up a nx kit and more gains :)

rev210 - going off the NOS guide, you had a rich-ish 120hp setup.

Incidentally, I just bought a dozen or so new jets and now have the correct setup installed (as of 30 mins ago) for 125hp.  It's mental.....  I mean.... off to the dyno!

Adrian

I seemed to remember I liked toluene at the time and so being on the rich side was a bonus since it likes a slightly richer AF ratio. I kept / lost the two I was using before the car was off the road. Those were a bit bigger again, 120 for the ones I sent over sounds about right.

Did you try those jets at all? I seem to remember cautioning you :D

Benm,

The fuel pump/ exhaust is really the only two areas of initial concern. My old bunky had the factory intercooler.Nitrous actually drops the intake temps quite alot by itself.

Nothing wrong with NX kits.

The guy who you use to tune the kit might suggest one brand or another but, if you can tune on you can tune them all I guess. The advantage may come if they have extra jets lying around to get the right size sussed.

It just seems as you are aimmimg to high with a standard motor. You want to run qucik times with a stock car and only nitrios fitted. I think nitrios is better suited to already built motors that can handle the extra power.  :crazy:  

GTSTBOY

You're speaking from experience then? What's aiming too high when I've already run 11's on 65hp gas? I never said how high I was aiming?!?!? If you're speaking from experience I'm more than prepared to listen...if you're not, well perhaps you could be a little more open-minded and learn something.

Not having a go at you buddy but I copped a lot of shit when I fitted the gas but have run some numbers since then that I am more than pleased with at a fraction of the cost of a built motor. Hell, a fraction of the cost of pistons and rods!!

Adrian

Not having a go at you buddy but I copped a lot of shit when I fitted the gas but have run some numbers since then that I am more than pleased with at a fraction of the cost of a built motor. Hell, a fraction of the cost of pistons and rods!!

Adrian

I aggree but the long term longivity of your motor seems that it is going to be short lived. It seems by spending money is to save money build it once and do it right.

How much is it to fill a 10lb bottle?

This is an example of ongoing costs what is it around $100 to refill

GTSTBOY

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