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GCtech Motorsports
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Discussion Starter #1
What Nitrous Is

Nitrous Oxide is the molecule formed by the bond between 2 atoms of
Nitrogen and one atom of Oxygen "enn two ohh" (Damn ASCII, no
subscripts)

Hmmm. 2 N, 1 O. 66% Nitrogen, 33% Oxygen... Say, doesn't that sound like
air? (75% N, 25%0) Why yes, it does! So all Nitrous is is chemically
compressed air. Sure enough, when Nitrous is exposed to heat, 2
molecules of Nitrous decomposes into 2 gaseous Nitrogen molecules and
one gaseous Oxygen molecule. Instant air, instant boost.

What Nitrous Does

Nitrous comes in a liquid form, and to keep it liquid requires fairly
high pressure. Squirting this high pressure liquid into a hot combustion
chamber causes it to decompose into gases, and at the same time, expand
greatly. This expansion in turn sucks a lot of heat out of the intake
charge, making it very dense.

End result: A lot of very high pressure, low temperature air in your
combustion chamber, in a very short period of time. A sort of chemical
intercooled turbo.

If more fuel is added at the same time as the nitrous, then you get a
whole lot more power. If for some reason you don't add more fuel at the
same time as the nitrous, you get a _very lean_ high pressure mixture,
which as anyone who read my detonation post should know is a Bad Thing.
Very Bad. Blow-heads-clean-off-the-block Bad.

So, your typical Nitrous setup has:
- a nitrous bottle
- nitrous injectors of some sort
- extra fuel injectors of some sort
- fuel and nitrous solonoids for shutting the stuff on and off
- various safty features to ensure that nitrous is never added
either by itself, or at part throttle
- sometimes, a device to reduce engine timing under boost.

Common Pitfalls

A low end nitrous setup is very easy to install, fairly easy to
calibrate, and the most bang for the buck to be had anywhere. That
initial ease of use is deceptive, however. The temptation to "just add
more" must be resisted, however, as it becomes easy to overpower the
fuel system and run lean if you don't think it out.

You guys who added 16G turbos and found you were leaning out 'cause the
stock injectors and pump couldn't flow the fuel required by the amount
of air the turbo was flowing - Nitrous has the same problems, except
that a lean turbo burns pistons, whereas a lean nitrous setup blows them
up. High nitrous levels have a nasty way of finding the weak spots in a
driveline, much the same as big turbos - just a little faster.

Using Nitrous with a Turbo

Yes, it can be done, although if you can pull it off, you're a better
man than me. A shot of nitrous means a big shot of exhaust is released,
which means in a few milliseconds your turbo is going to be producing a
whole lot of boost. You've now got _2_ boost-producing devices at once,
both of which are going to require extra fuel. That's a ton of power,
but you'd better not run lean...

I have seen systems that used nitrous like an acellerator pump. Stepping
on the gas squirted a little shot of nitrous into the engine, to help
spool up a big turbo faster. It was controlled by a boost sensitive
cutoff switch that killed the nitrous once the motor started producing
boost. Nifty, and a whole lot easier to manage.
 

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TTGTOonSteroids said:
I have seen systems that used nitrous like an acellerator pump. Stepping
on the gas squirted a little shot of nitrous into the engine, to help
spool up a big turbo faster. It was controlled by a boost sensitive
cutoff switch that killed the nitrous once the motor started producing
boost. Nifty, and a whole lot easier to manage
What exactly are they called & can you use them with any set up?
In other words could i use it with the nitrous kit i have? How much dose it run for something to manage the gas like that?

Whats the best way to hide gas on a 3K/Stealth?
I like to be sneaky.
 

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Re: Re: for all u guys that dont know what nitrous is and works ,,,here is some info ..

Sabotage said:

Whats the best way to hide gas on a 3K/Stealth?
I like to be sneaky.
U can see my setup when you come down or me going up to AAM :D......U wont see a thing
 

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Re: Re: Re: for all u guys that dont know what nitrous is and works ,,,here is some info ..

99missile said:
U can see my setup when you come down or me going up to AAM :D......U wont see a thing
When! When are you comming to AAM? I wana see !!!
Do you have purge kit n all?
I think i wanna see it after it's on the dyno & tuned, but i don't care i wanna see ither way.
 

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GCtech Motorsports
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1,666 Posts
Discussion Starter #6
the unit that controls the nitrous grdaually and then it shut it off automatically is a nitrous computer it costs from $340-500 bucks is made by nitrous ( nitrous master mind) and Jacob's electronics (jacob's master mind) .. and i when to turbonetics factory last week adn they told me they are working on a similar device and would cost around 300 bucks...............

Gradually*
 

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GCtech Motorsports
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1,666 Posts
Discussion Starter #7
sabotage

Hey man , u got me thinking on a good hidden nitrous system for our cars.... and i came op with something really nice .
out back seats are useless no leg room , so if u have ever taken the back bottom seat out it , the frame has a concave shape, is perfect to use little 3lbs bottles in both sides im talking enough little bottles to make a 10lbs bottle size... and just redo the seat to sit higher........
im gonna start working on it i sent u guys some pics when is done.......

take care
Gilbert
GtConcepts
 

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No surrender!
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Re: sabotage

TTGTOonSteroids said:
Hey man , u got me thinking on a good hidden nitrous system for our cars.... and i came op with something really nice .
out back seats are useless no leg room , so if u have ever taken the back bottom seat out it , the frame has a concave shape, is perfect to use little 3lbs bottles in both sides im talking enough little bottles to make a 10lbs bottle size... and just redo the seat to sit higher........
im gonna start working on it i sent u guys some pics when is done.......

take care
Gilbert
GtConcepts

All i ahve is a driver seat right now, I have no plans to put the back seats back in. :)


About that computer, Can i add it to just any Nitrous system?
 

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GCtech Motorsports
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Discussion Starter #9
if u have only the driver's seat , and the back is empty ,then i don't see the point of having a hidden nitrous oxide system:confused:
Anyways , yes u can add this Master Mind to any nitrous oxide system (NOS) it will work perfect....

later
Gilbert
GtConcepts
 

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how often do you need to refil though? and how much is it approximate cost if you are saying that you are driving nitrous like its almost as important as pumping fuel into your car..
 

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GCtech Motorsports
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Discussion Starter #11
well i refil three times a month is costs around 30-40 bucks to fill up the bottle, but I only use it when I race ,, thats twice or once ever week, but i pack two bottles every time i race, some times at night is to cool and the presure on the bottle drops to 600 and optimal levels is 1000-1200 so by using two bottles i can get the pressure to 1000 on very cold days.
Then again don't try this bouble bottle thing , is dangerous...
and yeah man Nitrous is a very important fuel to me..... once u use Nitrous is like a drug , u can't let go is so danm!!! good...
specialy on turbo cars I just bought two T66 turbines, and im using a 25-150 progresive Nitrous Oxide setup.... i can not wait to feel the power............ i should be done by next month..
.......................................NITROUS OXIDE..................................

takecare
Gilbert
GtConcepts
 

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I plan to put the seats back in when i'm done installing my speakers. I may/ may not put the back seats back in.
 

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gilbert, you gonna put the t-66s in the stock turbo locations? someone told me a person once fit t-78s in the stock locations! :eek:
 

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Wizard of NOS
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Good info!

Heres alittle more info to add to that. Basicly more ways to control nitrous, and make it work for you.

All stock factory engines are built with a safety factor when it comes to RPM, HP produced, cylinder pressure, engine cooling, etc. If you are only going to use a 100 HP nitrous setup on a 300 cubic inch or larger engine, built in factory safety factors are probably sufficient. As power output levels are raised engine modifications are usually prudent.

The most common mistake made when using nitrous oxide injection concerns ignition timing. A normally aspirated engine makes its best power when peak cylinder pressures occur between 14 and 18 degrees after TDC. KB Pistons usually require 34 degrees BTDC ignition timing at full mechanical advance to achieve proper ATDC peak cylinder pressure. The total time from spark flash to the point of peak pressure is typically 48 to 52 degrees. If an engine is producing 30% of its power from nitrous, the maximum cylinder pressure will occur too close to TDC to avoid run away detonation. If ignition does not get retarded, good-bye horsepower and head gaskets. The key to getting max HP from a max nitrous engine is to shift the maximum cylinder pressure event progressively further after TDC.

Cylinder pressure of 1000 PSI at TDC, can drop to 500 PSI with less than 3/8" of piston travel. If you can manage to get 1000 PSI in the same engine after the 3/8" travel, the pistons will have to travel an additional 3/4" to lower the cylinder pressure to 500PSI. Work is defined as a force times distance. An average pressure, (750 PSI X 12-1/2 sq. in.), times distance in feet, (3/8"divided by12), equals 293 foot pounds of work. Our second example, because it has twice the chamber volume above the piston location, must move twice as far to lower the cylinder pressure by 1/2. Since all the other numbers, by our own definition are the same, the force multiplied by a distance twice that of the first example will equal twice the work done, 586 foot pounds of work. There is no free lunch in horsepower equations because to get 1000 PSI above the piston in the second example takes twice as much fuel and energy as the 1000 PSI in the first example. What this offsetting of the peak pressure does is allow us to use the extra fuel mix available to a nitrous engine without breaking and melting things. The system that allows us to postpone maximum cylinder pressure is ignition timing retard. To a lessor extent short rod ratios, lower compression ratios, high RPM, aluminum heads, a tight quench, a rich fuel mixture, a small carburetor and hotter cams tend to delay maximum cylinder pressure.

consider that the ideal cylinder pressure would be just short of detonation pressure and this pressure would be maintained from top dead center, and as long as possible after TDC. If timing is really late, you won’t build enough cylinder pressure to start the car, let alone drive it. The 1000 PSI pressure in the example is not the maximum allowable combustion pressure but, rather, a comfortable pressure for illustration of the work principle.

Some nitrous manufacturers recommend, "retard the timing two degrees for each fifty horse power of nitrous". Other nitrous kits have the flame speed artificially slowed by the intentional use of a rich fuel to nitrous ratio. The maximum performance engine with a heavy nitrous load must achieve peak cylinder pressure progressively further after TDC. The heavy load engine will have the fuel and oxygen mix to make high cylinder pressures, with the combustion chamber size being drastically increased due to the piston being on its way toward bottom dead center. The strongest engines have less compression ratio, less spark advance, and more nitrous.

You can improve maximum power stroke efficiency and minimize exhaust pumping losses by running the engine at lower RPM and/or improving the exhaust valve size, lift and port design. A big nitrous engine likes everything about the exhaust to be big. If it flows good enough the cylinder will blow down by bottom dead center, even at high RPM with relatively mild exhaust valve timing. There are many variables in the design and development of an all out nitrous engine. A mistake will cause the melt down of any brand of piston. The high strength of the KB piston will withstand detonation and severe abuse. Unfortunately, all pistons will melt and when cylinder pressure limits are exceeded, run away detonation can occur. The excess detonation heat makes the plugs, valves and piston so hot the ignition system alone can not be used to shut the engine down. Continued operation worsens the situation to the point of a total melt down. Designing a maximum performance nitrous engine is more of an exercise in heat management than it is in engine building.

A lack of a sufficient fuel supply is probably the most common killer of the nitrous engine. If you add a 300 HP kit to your present 300 HP engine, your fuel requirements roughly double and a shortage doesn’t just slow you down, it melts things. An electric fuel pump and fuel line devoted entirely to the nitrous equipment is recommended. Some people add a small "race fuel" tank just for the nitrous. If you are using a diaphragm mechanical pump to supply fuel to the carburetor, it is worth while to increase the fuel line I.D. If the carburetor goes lean while the nitrous is on, the pistons can melt even with a rich nitrous fuel jetting. The large fuel line trick (1/2" dia.) only makes a major improvement in the operation of diaphragm mechanical fuel pumps. It is a waste of time on most electric applications. An electric pump pushing a mechanical pump is not recommended and does not do well at high engine RPM. A large size line is effective with a mechanical pump, even if you use smaller fittings at the tank, fuel pump and carburetor. The advantage of the 1/2" large line is not related to the steady state flow rate of the line. The advantage relates to the acceleration time and displacement of the pulsating flow common to the mechanical pump.

High compression ratios can be used with nitrous but shifting the maximum pressure after top dead center becomes more and more difficult. I prefer to use street compression ratios and then just work with adding more nitrous to get desired horsepower levels
 

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GTOTTonSteroid......

If you have a pressure problem why don't you use the bottle heater.I have one in my car with the cockpit switch.I usually shut it down when it reach 900-1000psi.This should help you to use the remain of the NOS left.
 

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GCtech Motorsports
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Discussion Starter #16
99missle

yeah man i have two bottle heaters... but i pack to units incase im low on one.. u know ,,,and when i dont feel like using the heater i open both units...............

omnip_1....... yeah man im doing two T66 not exactly they gonna go in the stock possition, i have to move the turbo upwards and an few inches to the left..........nothing big... it just requires time...

take care
Gilbert
gtConcepts
 

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TTGTOonSteroids said:
2 N, 1 O. 66% Nitrogen, 33% Oxygen... Say, doesn't that sound like air? (75% N, 25%0) Why yes, it does! So all Nitrous is is chemically compressed air
Interesting thread. One small correction though. Nitrous oxide is <B>nothing</B> like compressed air. The nitrogen in air is not bonded to the oxygen molecules. I didn't bother reading all the other details. Hopefully they are more factual. :)

The constituents of air (approximate values):
78% nitrogen,
21% oxygen
1% CO<sub>2</sub>, water vapor, and other gases.

Yes, you can do subscripts if you know how. :)
 
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