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Old 01-17-2014, 12:52 PM   #181 (permalink)
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any pressure build up (aside from normal compression) that occurs prior to tdc is counteractive, so, under certain conditions, you can get some improvement by increasing the rate of combustion. Also it is generally accepted that a pressure peak of about 10 degrees ATDC is most efficient.

Since lean burn is "slower", as is lower pressure, the pressure curve is wider (or as the curve is wider in relation to higher rpms), adding n02 to enhance combustion makes sense so that you can narrow the pressure curve and put more on the expansion side of tdc. Again, the effect depends on conditions.

As well as "leaning out" an engine is somewhat counter productive, the engine is oversized and moving more air than is needed for combustion. Lean AND high rpm is a bad combination.

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Old 01-17-2014, 04:10 PM   #182 (permalink)
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Very good points.

Quote:
Originally Posted by P-hack View Post
any pressure build up (aside from normal compression) that occurs prior to tdc is counteractive, so, under certain conditions, you can get some improvement by increasing the rate of combustion. Also it is generally accepted that a pressure peak of about 10 degrees ATDC is most efficient.

Since lean burn is "slower", as is lower pressure, the pressure curve is wider (or as the curve is wider in relation to higher rpms), adding n02 to enhance combustion makes sense so that you can narrow the pressure curve and put more on the expansion side of tdc. Again, the effect depends on conditions.

As well as "leaning out" an engine is somewhat counter productive, the engine is oversized and moving more air than is needed for combustion. Lean AND high rpm is a bad combination.
I would like to add that lean-burn engines can operate with little to no throttling resulting in much reduced pumping losses at a given power output. That is the whole idea behind pulse and glide driving - to use the engine in as open a throttle setting as possible.

Lean-burn is akin to cylinder deactivation in that a "large" engine can act like a much "smaller" engine by virtue of the greatly reduced fuel use at cruise settings without the complexity of cylinder deactivation.

And, yes, lower engine speeds (rpm) more easily allows the use of lean-burn.
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Old 01-18-2014, 11:34 AM   #183 (permalink)
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Quote:
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How does a faster combustion event lead to an efficiency improvement? How have you measured improved BSFC? This sounds like an opportunity for detonation, which will not improve fuel economy.
As P-hack posted "any pressure build up (aside from normal compression) that occurs prior to tdc is counteractive"

My own BSFC figures came from my data-logs while on a chassis dyno. Fuel usage verse power ABA testing.

I also have the ability to read knock with my engine management system in which there were no counts of knock while running the nitrous.

Today's engines are all running fast burn combustion type heads. This actually helps with preventing detonation, due to the less time during the combustion event the less likely the engine will detonate. Plus as P-hack said there will be less pressure as the piston cycles to TDC running less initial ignition advance.
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Old 01-18-2014, 12:39 PM   #184 (permalink)
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Possibly you do not have this available in your area. Fuel receipt and an odometer on our vehicle. Texas requires these on a motor vehicle and with that and the advent of math you can do some calculations based on the amount of fuel purchased and the number on miles driven with and with out the HHO turned on. When doing this over many tanks of fuel you can get a reasonable degree of accuracy. You run the gas produced thru a bubble chamber to take out the "Steam" if your system is designed to do that before it enters the intake. If you have studied this as long as I had you would understand the progression of the idea. Now I have to wipe off the key board. Got butter from my grilled cheese on it.

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Old 01-18-2014, 03:17 PM   #185 (permalink)
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Seriously, not a double blind test, not even a fuel log, or mention of driving style, or conditions, and you CLAIM it was getting you 40%, if it were not for that meddling computer. You may be glib, but you are part of the problem. So far this is just as convincing to me as your words:

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Old 01-18-2014, 05:18 PM   #186 (permalink)
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Quote:
Originally Posted by pgfpro View Post
... I have total control over ignition timing and fuel flow through my engine management system.
Is this a system which is commercially sold (e.g Emerald) or something you have created, or a hybrid of some kind ?

(I may have missed previous answers, in which case apologies).
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Old 01-18-2014, 08:21 PM   #187 (permalink)
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Quote:
Originally Posted by Arragonis View Post
Is this a system which is commercially sold (e.g Emerald) or something you have created, or a hybrid of some kind ?

(I may have missed previous answers, in which case apologies).
Sorry I didn't mention the system in this thread?

Its ECM LINK speed density V-3. It's utilizes a stock 90' thru 94 Talon/Eclipse eprom ecu. You remove the factory eprom chip then add a socket to it and install their chip.

I'm also using a ECX Haltech standalone to read other parameters exhaust back pressures, EGT etc... I'm running two wide-band O2 sensors. One is a AEM and the other a LC1 Innovate.
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Old 01-18-2014, 08:48 PM   #188 (permalink)
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Quote:
Originally Posted by Disco007 View Post
1. How does Nitrous Oxide work when injected? Liberated free "O" molecule

2. H 2 "O" could the extra "O" introduced into the system have an impact?
Plus the free Hydrogen should create a hotter burn like the Hindenburg?

I know that it's hard to believe that it works, but it does. 1991 Chevy Caprice 305 with homemade bubbler was getting 40% better fuel economy till the computer did not like the extra "O" in the system. To get it to work properly you need to "TUNE" the system for the extra "O". I'm not that competent to tune the computer yet.

All of you that argue against this need to take a good look in the mirror and see who is holding you back form real ECO modding? Don't worry I'm Human 2
Couldn't tell if you were asking or notů

Nitrous is an oxidizer, that is, it has a free electron pair to donate. Displacing ambient air (with 21% O2) with NOS (33% Oxygen) raises the fraction of oxygen available for combustion.

It also enters at @ -130║F, increasing the density (and hence, amount) of oxygen for combustion. IIRC, a 10║F drop in manifold air temp gives a 1% increase in HP. But don't trust my memory on this, but it's why on Friday nights guys spray down the intake with CO2 just before a run.

As Rusty alluded to prior, there are a lot of intermediary products in the combustion process, of which nitric and oxygen species as single unpaired radicals would exist. NOS may change the concentrations of the intermediaries, and I guess that it would drive the reaction more towards completion- but dunno for sure.

The addition of H2O does have profound effects on combustion, and has been very well documented for about a century now- but both good and bad. (not sure about Hindenburg but seem to remember something about metal paint which would be more sensible)

Are you running a HHO electrolyzer or a "Novak" kind of water vapor system? I'm not clear on this. But I think you're right- the O2 sensors will enriched the mixture when the extra oxygen is sensed.

In a vapor system as I understand, it allows a lean burn condition to occur. I can see how cooled, humidified water vapor could also inhibit detonation. It would also probably work best in a low demand state such as throttle closed and high manifold vacuum. But I'd also expect it to knock like hell under load.

I think we'd all be very interested if you could do some testing on this. Do a tank with the system on, then cork it and do a tank system off. Repeat this a few times while trying to keep your driving habits and styles the same. Keep an accurate log- very important!

What may be even better is if you could do this for a few months in both winter AND summer.

And yes, we're people too, but it's spelled "Houston". Sorry about that. I know it's kinda OCD, I'm a native and very proud.

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Old 01-19-2014, 02:19 PM   #189 (permalink)
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Quote:
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Sorry I didn't mention the system in this thread
Thanks - you may have done and I may have missed it due to man-flu in my head.

EDIT - to confirm this is a "standard ECU" from an Talon/Eclipse (Mitsubishi ?) but with an updated code chip installed via a socket ? How do you monitor the other things you mentioned.

Again not trolling, I get the basics of ECUs (and plan one for my MGB with a Zetec at some point when I have time, money and energy) and am gathering info.

Feel free to ignore, I am OT.
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Old 01-19-2014, 03:38 PM   #190 (permalink)
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Quote:
Originally Posted by Arragonis View Post
Thanks - you may have done and I may have missed it due to man-flu in my head.

EDIT - to confirm this is a "standard ECU" from an Talon/Eclipse (Mitsubishi ?) but with an updated code chip installed via a socket ? How do you monitor the other things you mentioned.

Again not trolling, I get the basics of ECUs (and plan one for my MGB with a Zetec at some point when I have time, money and energy) and am gathering info.

Feel free to ignore, I am OT.
No problem
My stock ecu with the ECM LINK chip installed gives me control on all these parameters. Plus real-time data-logging and real time tuning.

RPM/TPS:
Target idle,Launch Limit, Rev Limit, Coasting FC Offset, TPS adjustments

Fuel:
Global fuel, Fuel Injector Deadtime

MAF Fuel: not using not running MAF

MAF Clamp:same as above

Speed Density Table:
Load/RPM base table

AUX/Maps:
To run an extra set of injectors and have all control of their maps

Idle Air:
AC on rpm AF off rpm, Coolant based adjustment

Narrow band simulator:
Convert W/B to Narrow band sim if no narrow band O2 is used

Anti Lag System/ Knock Control:
rpm based map to turn on and off anti lag, Knock control activate at users set rpm and TPS %

Fuel Pressure Solenoid Control:
Turn on F/S rpm load base

EGR Control:
turn on and off rpm base, TPS and load base

Dash Controls:
Flash Engine light at knock count set by user, coolant temp set by user

MISC:
Lock in Open Loop Mode, Individual Injector Control, Diagnostic Control etc.

Report DTC:
EGR,TPS,FP,O2,Speed sensor,Knock sensor

ECU Inputs:
with after market 5 volt sensor's and user define naming and pin assignments

The next list I will just post the parmeter and not the table adjustments,
Air Flow Smoothing:
Base TipIn TPS Adjustments:
Coolant Temp. Fuel adjustment:
Fast idle ISC position:
INj. Battery adj.:
LTFT Select:
Load Scale:
Open loop Max OCT:
Open Loop Min OCT:
Open loop Thresholds:
SD Temp. Weighting:
STFT and O2 Feed Back:
Timing Max OCT:
Timing Min OCT:

My Haltech system I'm using to read high pressure turbo exhaust back pressure, (ECM Link reads engine back pressure), second LC 1 Wide band, second speed sensor, second baro map, high pressure map, low pressure map, turbo rpm's high and low, fuel pressure, oil pressure.



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