Nitrous/Turbo theories

I think that I have a basic understanding of both nitrous and super/turbocharging, but I am interested in the pros/cons of both.

Nitrous:

N2O is composed of one part Oxygen to two parts Nitrogen.
When N2O is split up into its separate elements, the reaction is endothermic in that it outputs less energy than originally invested into it, which creates a cooling effect on the intake charge.
Cooler air is more dense, allowing more air into the engine.
Nitrous can be damaging to your engine because...
Requires more fuel to avoid a LEAN air/fuel mixture upon ignition.


Turbocharging

The density of surrounding air is 14.7 psi at one atmosphere (atm).
A turbocharger functions by compressing air (belt-driven or exhaust-driven) into the engine.
Compressed air is hotter than normal, sometimes causing detonation.
Surrounding air is composed of roughly 21% oxygen.
Also requires more fuel to avoid a LEAN air/fuel mixture upon ignition.


MAJOR Effects

Since one is adding more air/fuel to a set volume (the bore of your cylinders), temperature is increased as a function of compression.
Engine internals are subject to break due to increased pressure in cylinders.


If the purpose of Nitrous/Turbo are to force more O2 into an engine, which does this more effectively? I have heard countless people say that Nitrous is much more destructive to your engine than a turbo, yet they both seem to do the same thing: more air in an engine. So I put forth this question: Is one method more damaging to engine internals than any other method? What can be done to prevent engine damage?

I think that I have a basic understanding of both nitrous and super/turbocharging, but I am interested in the pros/cons of both.

Nitrous:

N2O is composed of one part Oxygen to two parts Nitrogen.
true

When N2O is split up into its separate elements, the reaction is endothermic in that it outputs less energy than originally invested into it, which creates a cooling effect on the intake charge.
this isn't a nuclear reaction, none of the compounds are splitting. N2O has a higher concentration of oxygen than plain old air. for example, 1L of N2O and 1L of air, both at the same temp, the N2O will have 36% oxygen while air only has 21% oxygen. so injecting N2O into your engine will result in more oxygen in the engine.

Cooler air is more dense, allowing more air into the engine.
Nitrous can be damaging to your engine because...
Requires more fuel to avoid a LEAN air/fuel mixture upon ignition.


all true

Turbocharging

The density of surrounding air is 14.7 psi at one atmosphere (atm).

or commonly known as 1 bar (though technically it's 1.013 bar=1 atm)

A turbocharger functions by compressing air (belt-driven or exhaust-driven) into the engine.

supercharger-belt driven
turbocharger-IS a supercharger, but a different type of supercharger that uses exhaust gases to spin the turbine, u got the idea pretty much

Compressed air is hotter than normal, sometimes causing detonation.

called 'knocking', and an intercooler is used to prevent that

Surrounding air is composed of roughly 21% oxygen.
Also requires more fuel to avoid a LEAN air/fuel mixture upon ignition.


pretty good

MAJOR Effects

Since one is adding more air/fuel to a set volume (the bore of your cylinders), temperature is increased as a function of compression.
Engine internals are subject to break due to increased pressure in cylinders.


and so that's y internal upgrades are a must when you're adding large amounts of boost to your car. stock car could handle 6-7psi or a 50hp shot of n2o.


If the purpose of Nitrous/Turbo are to force more O2 into an engine, which does this more effectively? I have heard countless people say that Nitrous is much more destructive to your engine than a turbo, yet they both seem to do the same thing: more air in an engine. So I put forth this question: Is one method more damaging to engine internals than any other method? What can be done to prevent engine damage?

though nitrous is the best bang for your buck, IMO i'd go w/ turbo. unendless amount of tuning and upgrades to get more h/p and effeciency. used properly, neither turbo or nitrous will do any damage to your car's engine. however, ppl over-use their nitrous, bad, or run their turbos at too high of psi, also bad. key to not destroying your car is play it safe-though u might miss out on some extra precious few hp. but in the end, if u play it safe, u'll still have an engine. :grinyes:

krebs, the N2O molecule does split up like this:

2N2O(g) --> 2N2(g) + O2(g)

This decomposition does require heat and is therefore endothermic, but I'm not sure if that cools the intake charge. I DO know that the nitrous that comes out of the bottle is VERY cold, thus cooling the air it's entering.

The majority of engine damage caused by either method is due to improper tuning, resulting in detonation. The increased cylinder pressures are not really a concern at streetable levels of boost. Detonation is the number one killer of turbo and nitrous motors.

krebs, the N2O molecule does split up like this:

2N2O(g) --> 2N2(g) + O2(g)

This decomposition does require heat and is therefore endothermic, but I'm not sure if that cools the intake charge. I DO know that the nitrous that comes out of the bottle is VERY cold, thus cooling the air it's entering.


well its not really the nitrous being cold its the fact that its an expanding gas(after exiting the bottle of course) and all expanding gases have an endotermic effect

i did not know that the chemical decomposition of the N2O is endotermic too

and patton is right the most important factor...and sadly often overlooked....its a proper A/F ratio...run too lean and it will not matter how strong your engine is when it will get detonation

When something oxidizes (burn) we have an exothermic effect so it's quite natural the the reversed must be endothermic.

Nitrogen prefers to be in it's natural stage of N2, so the energy needed to separe it from the oxygen is quite small compared to the carbon and hydrogen in gasoline.

The separation of N2O happends under the later part of the compression stroke, that's also when most gasoline evaporate. This would therefore have none or a very small cooling effect on the intake air. The cooling effect on the intake air must therefore come from the expanding gas.

well its not really the nitrous being cold its the fact that its an expanding gas(after exiting the bottle of course) and all expanding gases have an endotermic effect

i did not know that the chemical decomposition of the N2O is endotermic too

and patton is right the most important factor...and sadly often overlooked....its a proper A/F ratio...run too lean and it will not matter how strong your engine is when it will get detonation
I said the nitrous coming out of the bottle was very cold, did I not?

I said the nitrous coming out of the bottle was very cold, did I not?


as a lawyer would say...."not to the best of my recolection"...

i'll stay with that;)










just joking:)...sorry in re-reading your post i can see that was what you meant....i was kind of surpised that you did not know that actually since you are obviosly quite knowlegeable about cars....well i was wrong my bad


now i'll go and ban myself:wave:

Nitrous is easier to set up.
cheaper, and can be turned off.
granted, a turbo timer will allow you to turn it off as well, but that is one more component whcih costs more money.
go with a 50 shot and have fun.

Nitrous is easier to set up.
cheaper, and can be turned off.
granted, a turbo timer will allow you to turn it off as well, but that is one more component whcih costs more money.
go with a 50 shot and have fun.

WHAT?!?! After reading some of your post you've left me scratching my head. I can't resist on this one.

You can NEVER turn a turbo off when the car is running, it is impossible. A turbo timer is a device for lazy people that don't want to sit and wait for the car to idle down so they buy a device that lets the car run and shut of after a certain amount of time to save the turbo from toasting its bearings.

A turbocharger does only deliver boost when it's needed, just press the throttle and it starts to do the work. When running normal the boost will drop and the turbocharger will just "run along".

As for costs this depends much on how often/long the extra power is needed. To fit a turbocharger doesn't need to be much more expensive than to fit a nitrous system. Then there will be no refill charge.

when I said turn it off, I meant that you can buy a device that will bypass the turbo at a given RPM.
My friend has that set up on his 300gtVR4.
He called it a turbo timer and may have been incorrect.
regardless, he said it allowed him to set the RPM at which he would activate his turbo.
thus allowing him to "turn it off"

when I said turn it off, I meant that you can buy a device that will bypass the turbo at a given RPM.
My friend has that set up on his 300gtVR4.
He called it a turbo timer and may have been incorrect.
regardless, he said it allowed him to set the RPM at which he would activate his turbo.
thus allowing him to "turn it off"

Like I said, you can't turn off a turbo. If the car is running there is exhaust gas moving past the exhaust wheel in the turbo causing it to spin. Turbos do not activate, they spool. I already told you what a turbo timer does, and it does not affect when a turbo will spool.

ok fine.
have it your way.

The equipment that you are thinking of is called a boost controller, and it allows you to control the amount of boost created by the turbine. To understand how a boost controller works, read this; http://www.automotiveforums.com/vbulletin/showthread.php?t=145031 . After reading this it is obvious that by design of the boost controller, it can only increase boost pressure by leaking pressure from the signal line. In order to lower the boost, the boost controller would have to add pressure to the signal line, which no boost controller is capable of doing. Because of this, it is obvious that a boost controller can not lower the boost level below the level determined by the original spring rate of the wastegate actuator.

The equipment that you are thinking of is called a boost controller, and it allows you to control the amount of boost created by the turbine. To understand how a boost controller works, read this; http://www.automotiveforums.com/vbulletin/showthread.php?t=145031 . After reading this it is obvious that by design of the boost controller, it can only increase boost pressure by leaking pressure from the signal line. In order to lower the boost, the boost controller would have to add pressure to the signal line, which no boost controller is capable of doing. Because of this, it is obvious that a boost controller can not lower the boost level below the level determined by the original spring rate of the wastegate actuator.
That's why cars with electronic regulated boost pressure use actuators with a lower spring rate.

krebs, the N2O molecule does split up like this:

2N2O(g) --> 2N2(g) + O2(g)


did i say anything in the contrary to that? that's basically what 'the new guy' said, and i comfirmed it. a single molecule of N2O is composed of 2 parts nitrogen and 1 part oxygen, but in the molecularly balanced equation, like you have (2 N2Og --> 2 N2g = O2g), the percent of oxygen and nitrogen is still greater than that in the atmosphere-making nitrous oxide a wise choice to increase the amount of oxygen taken in over normal inducted air.

did i say anything in the contrary to that? that's basically what 'the new guy' said, and i comfirmed it. a single molecule of N2O is composed of 2 parts nitrogen and 1 part oxygen, but in the molecularly balanced equation, like you have (2 N2Og --> 2 N2g = O2g), the percent of oxygen and nitrogen is still greater than that in the atmosphere-making nitrous oxide a wise choice to increase the amount of oxygen taken in over normal inducted air.
You said:

<<this isn't a nuclear reaction, none of the compounds are splitting.>>

Right on the first count, wrong on the second. The compound N2O does split, that's why it enhances combustion.

ahh, i did say that, well my mistake. what would i do w/out you casull?

ahh, i did say that, well my mistake. what would i do w/out you casull?
Flounder about, no doubt.

like flounder from animal house?! i wouldn't mind living like that...

like flounder from animal house?! i wouldn't mind living like that...
Flounder as in, having 2 eyes on the same side of your head.

ok, so he should have said boost controller instead of turbo timer, my mistake.
Are you certain that there is NO way to bypass a turbo? You would think that you could plumb a bypass that could be turned on and off, similar to the way a thermostat works in your cooling system.
although I am not sure why you would want to effectively turn your turbo off, unless you had something else going on (like nitrous).

You can bypass a turbo. Porsche did it early in the history of the automotive turbocharger to combat lag.

You can bypass a turbo. Porsche did it early in the history of the automotive turbocharger to combat lag.
You're thinking of the sequental setup on Porsche 959; the engine had two turbochargers and the flow to one of them was blocked at low flow requirements.

The first practical turbocharged road car eventually appeared in 1975 - the Porsche 911 Turbo 3.0. To reduce turbo lag, Porsche engineers designed a mechanism allowing the turbine to "pre-spin" before boosting. The secret was a recirculating pipe and valve: before the exhaust gas attains enough pressure for driving the turbine, a recirculating path is established between the fresh-air-charging turbine's inlet and outlet, thus the turbine can spin freely without slow down by boost pressure. When the exhaust gas becomes sufficient to turbocharge, a valve will close the recirculating path, then the already-spinning turbine will be able to charge fresh air into the engine quickly. Therefore turbo lag is greatly reduced while power transition becomes smoother.

http://autozine.kyul.net/technical_school/engine/tech_engine_3.htm#Overview

so it IS possible.
thanks. that sounds pretty neat, i wonder why they don't do it anymore?

so it IS possible.
thanks. that sounds pretty neat, i wonder why they don't do it anymore?

Yes, you can bypass the turbo, but you can't actually turn it off when the car is running.

Yes, you can bypass the turbo, but you can't actually turn it off when the car is running.
Yes, you can. Have somebody shoot holes into the hood and hope the bullets pierce the exhaust header(s)/manifold(s). :)

like speed holes?
:)

I was going to say that - I just couldn't remember the term. :)