There are three points. First, nitrous oxide is comprised of 2 parts
nitrogen and one part oxygen (36% oxygen by weight). When the nitrous
oxide is heated to approximately 572F (on compression stroke), it
breaks down and releases its load of extra oxygen, However, it is not
this oxygen alone which creates additional power, but the ability of
this oxygen to burn more fuel. By burning more fuel, higher cylinder
pressures are created and this is where most of the additional power is
realized. Secondly, as pressurized nitrous oxide is injected into the
intake manifold, it changes from a liquid to a gas (boils). This
boiling affect reduces the temperature of the nitrous to minus 127
Degrees F. This "cooling affect" in turn significantly reduces intake
charge temperatures by approximately 60-75 Degrees F. This also helps
create additional power. A general rule of thumb: For every 10 Degrees
F. reduction in intake charge temperature, a 1% increase in power will
be realized. Example: A 350 HP engine with an intake temperature drop
of 70 Degrees F, would gain approximately 25 HP on the cooling affect
alone. The third point, the nitrogen that was also released during the
compression stroke performs an important role. Nitrogen acts to "buff
or damper" the increased cylinder pressures leading to a controlled
combustion process and better slower heat release
Why N20?
Nitrous oxide injection has become a very popular option for today's performance enthusiast for several reasons:
N20 offers you more performance per £ / $ spent, than any other performance modification.
N20 installations are relatively easy to accomplish.
Since N20 is used only when needed, it offers you
the advantages of complete drivability and normal gas mileage while not
"on the button."
Systems available for virtually any power need from 5 HP to over 500 extra HP.
One of the few performance options available for today's computer controlled, fuel injected engines.
Systems can easily be removed or transferred to another vehicle unlike conventional tuning parts.
Q: Will N20 affect engine reliability?
A: Theoretically not.
In
moderate doses, properly set up and used by someone that understands
the system then it should not have any adverse effects. In some cases
the opposite could be argued.
But
probably... One day its inevitable your engine will break, they almost
all do so if you drive it like you hate it! No engine goes
forever so just accept it! If it has N20 fitted it will inevitably get the blame!
And It may well be nothing to do with the nitrous and usually isn't!
Q: Can I simply bolt a N20 kit onto my stock engine?
A: Yes. Provided its fit, healthy and one or two simple precautions are
observed then no problem In fact Stock engines are often best!
Q: What are some of the general rules for even higher H.P. gains?
A: Generally, forged pistons are one of the best modifications you can
make. Retard ignition timing by a few degrees. In many cases a
higher flowing fuel pump may be necessary. Higher octane (100+) racing
type fuel may be required as well as spark plugs 1 to 2 heat ranges
colder than normal with gaps closed to .025"-.030".
Q: How much performance improvement can I expect with a nitrous system?
Loads..... Depends on jetting. You simply choose!
Q: How long will the bottle last?
Approximately 10bhp per lb per min.
So
a 2.25 lb bottle on a bike will give just less than a minute with a
25BHP increase. Thats a LONG time when it goes from zero to 150mph
in ten seconds!
Q: How long can I hold the Nitrous button down?
A: It is possible to hold the button down until the bottle is empty. However you will be lucky to find enough road...
Q: When is the best time to use nitrous?
A: At wide open throttle only. Due to the tremendous amount of
increased torque, you will generally find best results, traction
permitting, at early activation off the line when drag racing.
Q: Will I have to re-jet my carburettor on my car when adding nitrous?
A: No! The N20 system is independent of your carburettor and injects its own mixture of fuel and Nitrous.
Q: Is nitrous oxide flammable?
A: No. Nitrous Oxide by itself is non-flammable. However, the oxygen
present in Nitrous Oxide causes combustion of fuel to take place more
rapidly inside the engine.
Q: Will nitrous oxide cause detonation?
A: Not directly. Detonation is the result of too little fuel present
during combustion (lean) or too low of an octane of fuel. Too much
ignition advance also causes detonation.
Q: Where can I get my bottle refilled?
A: There are many performance shops that can refill your nitrous bottle. There are many suppliers, see the "REFILL" page.
Q: Is there any performance increase in using medical grade nitrous oxide?
A: None! All the same, Medical grade simply does NOT have the bad smell chemical added that Race grade stuff does.
Q: Is it a good idea to use an aftermarket computer chip in conjunction with a Nitrous System?
A: Only if the chip had been designed specifically for use with nitrous
oxide. Most aftermarket chips use more aggressive timing advance curves
to create more power. This can lead to potential detonation. You may
wish to check with the manufacturer of the chip before using it. The
top manufacturers, such as APE & Super Chips do make special chips
for use with nitrous.
Q: Does nitrous oxide raise cylinder pressures and temperatures?
A: Yes. Due to the ability to burn more fuel, this is exactly why nitrous makes so much power.
But
the richer you run it the less heat. So if you want more power use more
of both. Do not just try to weaken the mixture to the limit as richer
is safer!
You
want pressure, its what makes the car/bike faster, but you don't want
the heat. Go Richer and more retarded the more boost you add!
Q: Are there any benefits to chilling the nitrous bottle?
A: No. Chilling the bottle lowers the pressure dramatically and will
also lower the flow rate of the nitrous causing a fuel rich condition
and reducing power. On cold evenings you might run on the rich side.
For optimal running conditions, keep bottle pressure at approximately
800 psi.
Q: Are there benefits to using nitrous with turbo or supercharger applications?
A: Absolutely! In turbo applications, turbo lag is completely
eliminated with the addition of a nitrous system. In addition, both
turbo and superchargers compress the incoming air, thus heating it.
With the injection of nitrous, a tremendous intercooling effect reduces
intake charge temperatures by 75 degrees or more. Boost is usually
increased as well; adding to even more power.
Q: What effect does nitrous have on an engine with considerable miles on it?
Mileage
is not an indication of engine condition. Some low mileage vehicles are
technically worn badly. Stop Start motoring, lack of oil changes or bad
manufacturing causes this. Some very high mileage cars and bikes that
have spent their lives on motorways and serviced regularly are found to
be almost as new when stripped down. Worn engines may be a problem,
high mileage may well not be. If you are unsure have a Garage
compression test, and oil pressure test it and get the Mechanics
opinion of its condition.
Q: Will the use of nitrous oxide affect the catalytic converter?
A: No. The increase in oxygen present in the exhaust may actually
increase the efficiency of the converter. Since the use of nitrous is
normally limited to 10-20 seconds of continuous use, there usually are
no appreciable effects. Temperatures are typically well within
acceptable standards.
Q: Can high compression engines utilize nitrous oxide?
A: Absolutely. High or low compression ratios can work quite suitably
with nitrous oxide provided the proper balance of nitrous and fuel
enrichment is maintained. Nitrous kits are used in applications from
relatively low compression stock type motors to Pro-Modified, which
often exceed 15 to 1. Generally, the higher the compression ratio, the
more ignition retard, as well as higher octane fuel, is required. For
more specific information talk to a qualified technicians.
Q: What type of cam is best suited for use with nitrous oxide?
A: Generally, cams that have more exhaust overlap and duration.
However, it is best to choose a cam tailored to normal use (when
nitrous is not activated) since 99% of most vehicle operation is not at
full throttle. There are special cam grinds available for Nitrous
competition which have more aggressive exhaust profiles etc. Since cam
selection depends largely on vehicle weight, gearing, etc., it is best
to stick to cam manufacturer's recommendations for your particular
goal.
Q: What type of nitrous system is better; a plate injection system, single point or a direct port injection system?
A: Neither is better. The best system is whatever "suits" your induction system the best.
Q: Should I modify my fuel system to use nitrous oxide?
A: Most stock fuel pumps will work adequately for smaller Nitrous
applications. It is important to check to see if your pump can flow
enough fuel to your existing fuel system (whether carburettor or fuel
injected), as well as being able to supply the additional fuel required
by the nitrous kit under full throttle conditions. It may be a good
idea to dedicate a separate fuel pump to the nitrous kit if in doubt.
Q: What are the advantages of using nitrous compared to other performance options?
A: The cost of many other performance options can put you in the
poorhouse. You can't buy more performance with less money than nitrous.
With a nitrous system, performance and reliability can be had for a
much more reasonable price while retaining the advantages of a stock
engine during normal driving. And, nitrous offers tremendous gains in
torque without having to rev the engine to excessive rpm's. These
factors help your engine last longer than many other methods of
boosting horsepower.
Q: How do I know how much nitrous is left in the bottle?
A: The most reliable way is to weigh the bottle to determine how many
pounds remain. When a bottle is near empty (about 20% or less nitrous
remaining) a surging effect is normally felt.
Q: What is the function of the blow-off safety valve on the bottle?
A: It is very important not to overfill a bottle; i.e., a 10 lb.
capacity bottle should not be filled with more than 10 lb. of nitrous
oxide by weight. Over-filling and/or too much heat can cause excessive
bottle pressures forcing the safety seal to blow and releasing all the
contents out of the bottle.
Q: Will I have to change my ignition system?
A: Most late model ignition systems are well suited for nitrous
applications. In some higher HP cases, it may be advisable to look into
a high quality high output ignition system.
FAQ Technical Fact/Fallacy (Don't know where this one came from originally but now I have modified it, it's ALL true!)
Nitrous
oxide injection has become one of the most popular methods of
increasing the power output of an internal combustion engine, and
justifiably so. Nitrous oxide (N2O) injection is simple precisely metered N2O
and gasoline are force-fed into the engine, supplementing the normal
air/fuel mixture to release more work-producing heat during the
combustion process. The only equipment required is an N2O storage tank, a pair of solenoid-actuated valves to control the N2O and gasoline flow, nozzles (or spray bars) to distribute the N2O
and gasoline, and the various hoses, lines and wiring to connect the
system. Engine disassembly is not required for installation-and the
system can be removed for resale or transfer to another car at any
time. The cost of a new professionally prepared system is reasonable
(between $400 and $600 US in most cases), and the power increase is
dramatic (usually in excess of 100 hp for most street systems).
As popular as N2O systems have become (industry estimates are that over 20,000 systems are now in use!), many enthusiasts still think of N2O
as some sort of evil black magic. Honest and reliable information about
the effects of nitrous oxide, the care and installation of N2O systems and tuning tips regarding N2O
use has been practically nonexistent. Instead, the bench racers pass
along inflated rumours of unbelievable power gains that rival a Saturn
rocket, and incredible horror stories of vehicles supposedly erupting
in fireballs that would make a hydrogen bomb seem small.
FALLACY: N2O is explosive and a fire hazard.
FACT: N2O will not burn, nor is it a fuel. It is
merely an oxygen-rich compound that supports the combustion of
additional fuel. That's why additional fuel is injected along with the N2O on all N2O systems. It is true that if N2O
is added to a combustion process already in progress, the extra oxygen
may cause rapid, uncontrolled combustion, thus raising the peak
temperatures produced.
FALLACY: N2O adds octane to the fuel being used and reduces detonation.
FACT: N2O does not increase the octane of the fuel
being used. However, nitrous oxide injection may suppress detonation
due to the intercooling effect of the depressurizing of the compressed N2O and by the introduction of extra gasoline. Most N2O
systems intentionally add about 10 percent excess fuel as a safeguard
against accidentally leaning the mixture. The extra fuel acts almost
like water injection to cool the mixture and dampen detonation.
FALLACY: Premium fuel must be used with N2O injection.
FACT: The purpose of N2O injection is to support
the combustion of extra fuel, thereby releasing more work-producing
heat in the combustion chambers. Consequently, maximum cylinder
pressures with N2O will be higher than when it isn't in use.
Extra cylinder pressure does tend to cause pre-ignition and
uncontrolled combustion, but as previously described, N2O injection also tends to suppress detonation. With most street N2O
systems, these two opposing forces tend to cancel each other out, which
means you can continue to use the same octane gas that was acceptable
before the N2O was added. Because competition N2O systems inject a greater quantity of N2O and gasoline than do street N2O
systems, cylinder pressure is frequently raised to the point where a
higher octane fuel (or anti-detonation additives) must be used.
FALLACY: N2O will melt pistons, rings and valves.
FACT: If the N2O system has been properly designed to supply the correct amount of gasoline along with the N2O, combustion temperatures will actually be lower than when N2O isn't being used, so damage from elevated temperatures does not occur. Since the purpose of N2O injection is to make more heat, this may sound like a contradiction, but it isn't. With N2O,
the total amount of heat energy released is greater, but the peak
combustion temperature is lower. Think of it this way: A huge oil
storage tank burning at an average temperature of 1000 degrees releases
a lot more energy than a small acetylene torch with a tip temperature
of 2000 degrees. That's a comparison by extremes, but in an engine with
N2O injection, each cylinder might be burning 25 percent
more fuel at a temperature of 1400 degrees than the engine would
without N2O at 1460 degrees.
Claims of engine damage while using N2O are not
totally fictitious, however, since if cylinder pressure does rise above
the octane tolerance of the fuel being used, detonation occurs, and
that will damage pistons, rings, etc.
FALLACY: Freezing the N2O tank increases N2O flow and the power output.
FACT: Whenever a pressure vessel is cooled, internal pressure drops. Most N2O
systems are designed to work with tank pressures of 600-800 psi, which
is the approximate pressure of a normal bottle at room temperature
(approximately 72 degrees). If the bottle is cooled below room
temperature, the pressure quickly falls, and flow would be reduced to
the nozzles. For example, a bottle that had 800 psi at 75 degrees would
fall to 450 psi at 30 degrees, and only 275 psi at O degrees.
On the other side of the coin, heating the bottle increases the pressure, but heat also tends to make the N2O vaporize in the line between the solenoid valve and the discharge nozzle, which upsets metering and reduces N2O
flow. Ideally, the bottle and lines should be kept at room temperature.
At the drags, some cooling of the bottle may be required to achieve
this while the car sits in the staging lanes, but a damp cloth or towel
wrapped around the bottle will generally be all that's required. If you
really want to pursue additional cooling, chill the line between the
solenoid
valve and the nozzle, and keep that line as short as possible to reduce
the likelihood of vaporization before the discharge nozzles.
FALLACY: N2O
injection in the individual manifold runners, as close as possible to
the cylinder head, is more effective than injection immediately below
the carburettor.
FACT: Although it used to be thought that direct port injection
improved performance by assuring equal distribution, subsequent vehicle
and dyno tests have shown that under-the-carb injection seems to
provide a greater power increase since the gasoline has more time to
vaporize as it travels down the intake runners. But the difference is
very small!
FALLACY: As long as there's still pressure in the N2O bottle, some N2O is left and the system will function properly.
FACT: An N2O system meters and discharges liquid N2O when everything is working properly. When filled, an N2O bottle is only 68 percent full of liquid. The remaining space is specified as an expansion area. Additionally, an N2O tank needs a siphon tube to assure that the pressure head in the expansion area forces liquid N2O out into the lines, rather than gaseous N2O. When the liquid N2O is expended, it is not uncommon for the tank to still have 600 psi pressure, so pressure alone is not an indicator of N2O. Gaseous N2O is clear, whereas liquid N2O,
vaporizing as it leaves the nozzle, will be white in colour. This is a
more accurate indication of whether there is still liquid N2O in the bottle.
FALLACY: You need a prescription to buy N2O.
FACT: A prescription is not required to buy industrial grade nitrous
oxide for automotive use. Nitrous oxide is available at most compressed
gas suppliers, such as welding gas supply houses, but we have heard of
isolated cases where a particular dealer who doesn't want to be
bothered servicing hot rodders will use the excuse that you must have a
prescription. If medical grade N2O
(the only difference is the sterilization of the bottles) was being
sought, then a prescription would be required. To make the purchase of N2O even easier, many speed shops are now refilling N2O bottles. If you live in a really isolated area or are confronted by an uncooperative dealer, the N2O system manufacturers will refill your tank, but of course, shipping the bottle back and forth is an inconvenience.
FALLACY: N2O requires no special tuning adjustments.
FACT: Force feeding N2O and extra fuel into the
combustion chambers increases the density of the mixture, which
increases the burning rate of the mixture. Consequently, it is
frequently necessary to retard the ignition timing slightly for optimum
results. The greater charge density also imposes a heavier load on the
ignition system, so a good high-energy ignition system, with good spark
plug wires and clean spark plugs is essential. If a competition N2O
system is being used, the plug gap should smaller, and plugs one or two
heat ranges colder than stock are recommended to help dissipate the
extra heat of combustion.
FALLACY: You can't build your own N2O system
FACT: YES!!! If you're sharp enough, you can as LOADS of people have done using these pages!
FALLACY: If tank pressure exceeds 850 psi, the solenoid valves will leak, flooding the manifold with N2O.
FACT: The solenoid valves used on some systems are rated at 850 psi
working pressure. Other systems have solenoids with even higher
ratings. In truth, the ratings are conservative and even the lowest
rated solenoids being used will work at pressures up to 1500 psi. The
working pressure has nothing to do with the pressure at which the
solenoid will leak, since pressure actually helps close the valve, so
the higher the pressure, the more tightly it seals. The working
pressure or rating only refers to the solenoid's ability to open the
valve against the pressure in the system.
FALLACY: N2O will blow up your engine.
FACT: If the N2O solenoid valve leaks or malfunctions while the engine is off, the manifold can become charged with a very lean mixture of N2O
and gasoline. When the ignition is first turned on, a spark impulse may
occur in a cylinder where the intake valve is standing open, igniting
the mixture, which will virtually explode. Carburettors have been blown
off manifolds in such situations. Consequently, it is advisable to turn
off the main valve on the N2O tank whenever the car is going
to be parked for several hours. If a leak is ever suspected, simply
remove the coil wire and crank the engine for about 10 seconds to clear
any N2O contamination.
FALLACY: You can smell leaking N2O.
FACT: Nitrous oxide is an odourless, colourless gas.
FALLACY: There's no limit to how much power you can make with N2O.
FACT: More N2O and more fuel equates to more
power, but there's a definite limit to how much any engine will stand.
It all comes down to: How fast do you want to go? And at what price?
