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Discussion Starter · #1 ·
Hi there,

I just wandered over here from ProbeTalk (hopefully there is no rivalry that'll get me lynched :) ), and I thought I'd say hi.

How many other forced induction guys are here?
 

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you consider ram air forced induction too right?
 

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Discussion Starter · #3 ·
Not really... the amount of pressure generated from a ram air setup is very minimal, even at high speeds. Certainly no fueling mods are required to support a ram air setup.

Cheers,
Andrew
 

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you can get about 3 psi right? enough to compensate for negative pressure (vacuum) in the intake manifold. its not 20 PSI but its forced.
 

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Discussion Starter · #5 ·
It might get you up to atmospheric, but you probably have to be going pretty darn fast. A while back I read an article analyzing the TransAm Ram-Air, and it boiled down to a couple horsepower (on that big engine) at 100+ mph. You'd probably gain just as much replacing the VAF with a MAF.
 

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good point. but i already have a MAF. ands whats a VAF?

also can i have your opinion on the following: is an engine still naturally aspirated if nitrous oxide is used?
 

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Discussion Starter · #7 ·
What kind of a car are you driving?

A VAF is a Vane AirFlow sensor. It is a spring loaded flag or plunger which measures how much it is pushed aside by the incoming air, and it reports this volume measurement to the ECU. The ECU must then combine this information with temperature and barometric measurements to determine the air mass that has been ingested.

Naturally aspirated means the engine is drawing air in on its own. With a compressor this obviously isn't the case. With NOS its a little fuzzier: the NOS is part of the combustion, plus it is cooling the intake air charge. This cooling effect tends to increase the density of the air charge, but the air is still being drawn in just by the engine. So I'd have to say that NOS is not forced induction, which means it is natural aspiration... unless you want to invent a new term to describe it. :)
 

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i was under the impression that NOS isnt ignited, but enters the combustion chamber at a very cool temperature. the ignition of the fuel causes heat i.e. causing the NOS to expand at a high rate. im driving a built 93 MX-6 4-cyl (about 2.3L i think).
 

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Discussion Starter · #9 ·
I just said that NOS is "part of the combustion"... its in there mixing it up with everything else. I don't actually know if it burns or not. I don't have any experience with NOS.
 

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A little NOS primer:

NOS is not flammable. It doesn't "burn" per se.

NOS (N2O) is a good carrier, by volume, of oxygen. When you spray NOS into the engine, the heat in the chamber during combustion dissociates the N2O, freeing up the oxygen. If you add more fuel, the freed oxygen oxidizes (burns) it, creating more power.

If you don't add enough fuel, you end up with a lean condition that causes very high combustion chamber temperatures and you also have free, unallocated oxygen that can oxidize things other than fuel: hot exhaust valves, spark plug electrodes etc. This is why you need to add extra fuel when the NOS turns on and why, if you don't, you can quickly wreck engine parts due to heat.

A second benefit is the very, very low boiling point of N2O. When fogged, it sucks a ton of heat from the intake tract making the charge density that much higher.

In my book, when you spray NOS, you are adding oxygen the engine wouldn't have ordinarily been able to obtain on its own. Not technically forced induction but not really normally aspirated either.
 

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Bravo! Took the words right out of my mouth mike!

How about this: NOSperated!!

A nifty fact, N2O approx. 34% oxygen compared to around 15% for normal air. More oxy means more fuel can be burned, therefore the added power!

Speedymx
 

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15% in normal air??

I know this is not a big deal, but unless your living someplace other than earth O2 composes 19-21% of the atmosphere, and even slightly higher very close to te ground (where our cars are "breathing"). Still the point was made 35% opposed to 20% Oxy is a great gain.
 
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