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#1 Jack in Norfolk

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Posted 04 October 2003 - 05:44 PM

how do old subies take to nitrous? I started thinking about how light the old ea81 turbo cars are and my mind started to wander. I started thinking about4 wheel traction, less than 2000lbs, a turbo charger, and nitrous???
wow. I guess that is how they ended up with the wrx.
Does anyone have nitrous runnin in an ea81 or ea82? Can they take it? Just wondering how and aluminum block and head would take all that compression.

#2 Mike W

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Posted 04 October 2003 - 07:51 PM

I've wondered how come nobody here in Seattle has done that. I mean EA81s used to be abundant and cheap, so why not feed 'em nitrous and when it nukes, say oh well and swap in another motor. Course now that EA81s are getting more scarce I'd say that's sick and destructive...but sure would be fun while it lasts.

#3 incognito



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Posted 04 October 2003 - 09:40 PM

any engine can handle nos.. its how much nos...

the nitrous freezes the oxygen and packs it into the motorr and BOOM!

NX says: no more than 20hp gain per cyl on a stock engine. That would be 80hp.. so a 25 shot or even a 50 shot is possible.

Look up Nitrous Express... read their faq, it will tell u more on how it works.

I already have this in plans for my EA82.

#4 Qman


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Posted 05 October 2003 - 03:49 AM

The only problem with using NOs is that it is short lived, a little expensive and can be very destructive. But other than that it works for racing but would be less than desirable off road unless it can be dialed down for shorter bursts.

#5 incognito



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Posted 05 October 2003 - 05:06 AM

eh, nos is like double propane (the cost).

Like i said before, you can put nos in a stock engine, but if you put too much, it will be destructive

#6 Jack in Norfolk

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Posted 05 October 2003 - 10:30 AM

what happens when you add it to a turbo?

#7 Skip


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Posted 05 October 2003 - 10:49 AM

FYI Nitrous itself is [u]not[/] combustible, you must add more fuel when you inject it.
from the NE website
"Q. Why does my engine need more fuel while on the bottle?
A. The fuel, or gasoline, is the source of the additional horsepower. The nitrous' job is to provide the oxygen to allow the fuel to be burned."

Just keep this in mind if you decide to DIY
a lean engine is not a happy engine
NE website referenced

#8 LameRandomName


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Posted 05 October 2003 - 11:56 AM

There's three important things to keep in mind about nitrous:

1) Your engine must be built to handle the power it makes ON the nitrous.
That sounds obvious, but people forget it a lot. It means that if you have a 200hp engine and you add 100hp worth of nitrous, which gives you 300, your engine must be built as if it were making 300hp all the time.

2) If something happens to your fuel supply and you go lean while on the juice, you probably wont be able to get off of it in time to save your engine. So choose injectors that lock in the open position if they lock up at all and use a fuel pressure cutoff switch that kills the power to the nitrous solenoid if the fuel pressure drops too low.
On the same subject, I personally will NOT build a nitrous system that doesn't have it's own independant fuel system, to include it's own fuel cell that I can keep stocked with 100 octane gas.
(100 being the highest unleaded octane I know of)

3) An engine can only "eat" enough nitrous to add about 50% more power.
That means that if you have a 200hp engine, you can add another 100hp in nitrous, IF your system is well designed, maybe another 110 if you're lucky, but you are NOT going to double your power or even come close.

#9 asavage


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Posted 05 October 2003 - 10:05 PM

Originally posted by Battle_Wagon_Medic
the nitrous freezes the oxygen and packs it into the motorr and BOOM!

Air is about 1/3 oxygen, the rest being mosty nitrogen.

NO2 is 2/3 oxygen, plus it gets to the engine a lot colder than the surrounding air (in most cases), so it's denser.

The net effect is that you can get more oxygen, and colder, less preignition-prone oxygen, into the cylinder.

Then you have to find a way to get more fuel there, too. Modern intake manifolds are not designed for fuel flow, only air flow, so if you dump fuel in up at the throttle body area (on a MPFI setup), the fuel is not going to have good distribution, will tend to settle out and not vaporise, etc.

On an SPFI setup, adding more fuel at the throttle body would be a good choice.

Back in the day (maybe 25 years ago) when I was looking at NO2 systems and turbos, the trick setup was to inject the nitrous near the compressor, and the fuel somewhere downstream. This was before mainstream FI other than Bosch systems.

I venture that there are not very many long-term NO2-enabled engines running around. It's not a gentle shove, it's more like a hammer blow, and it's not easy on engines nor drivetrains. But fun, in the short-term.

#10 DerFahrer


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Posted 05 October 2003 - 10:52 PM

Everyone is exactly right. NO2 simply adds a whole bunch of oxygen to the air/fuel mixture, therefore causing a VERY lean condition. The ECU will compensate by adding more fuel, but it can only do so much through a factory fuel system...

Therefore I would never give any car the laughing gas without making absolutely sure the fuel system can handle it, i.e. upgrade the injectors, pump, rails, etc. etc.

#11 Caboobaroo


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Posted 05 October 2003 - 11:09 PM

so ok, this is all dandy for the FI systems. What about us guys with carbs ie a weber and a bit more rabid hamsters under the hood?

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