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Old 02-25-2008, 06:37 PM   #1
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Smog and Fuel Economy

Now until I discovered Gassavers, I thought fuel injection was the best that you can get. Then I learned about lean burn and low emissions. Coming from California, I grew up with the California versions of cars getting worse mileage and lower performance. That's when I discovered HF,VX, and HX technologies using learn burn that I thought was not possible. It was quite a discovery, now as I prepare to get my next car built for economy I have a few questions about burn ratios and the emissions generated.

Now this may seem odd, but logically if a car were to burn more fuel, like in Cailfornia, it seems it would pollute more. Now I find that when you lean out a car it pollutes more. From what I understand the NOX goes through the roof, but over that lean burn, pushed beyond lean is the area that does not pollute.

So I figure in California they want the engines to run rich to keep the catalytic converters running all the time? Why are the HF,VX, and HX not allowed to run in the lean mode there, is it the transition between normal 13 to 1 and the cross over to 16+ to 1 where the California smog laws don't want the car producing excess NOX while transitioning?

Now in all the experiments, like using an EFIE, or HHO to tell the O2 sensor to lean out, where is the balance? Is there good smog bad smog? I understand that CO production is a constant and that the NOX is what there after to reduce.

So in this long roller coaster question, what am I doing when I'm running lean? Is there a perfect ratio where I'm getting great f/e and low emissions? The tricks like IAT tweaking, XFI cam, and all the other things to make a car get better mpg, are they polluting? I always thought that if you had a car going down the road like my old VW getting 24 mpg stock, modify it and get 34 mpg, that the distance that gas is being burned produces less polution for each given mile. If someone can set me straight on ratios, when NOX is produced, and how lean is lean, I would greatly appreciate it.
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Old 02-25-2008, 06:40 PM   #2
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I was looking at some curves the other day, nominal curves for an average motor, and there was seeming to be a sweet spot aroung 17-18:1 where you're surfing the other side of the NOx hump and just avoiding running into excessive HC emission from misfire problems.
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Old 02-25-2008, 08:22 PM   #3
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Research WHY there are catalytic converters and you'll learn some interesting info. NOX emissions occur because Nitrogen is the main component of air.

However, gasoline engines are inefficient so that we will burn more gasoline, and so that they will wear faster. Research CNG, LPG (natural gas and propane) conversions and you'll see that the engines don't wear out nearly as fast, and you'll run across the 376.59 MPG car built in....1973. The reason that we don't have lean burn is so we'll use more gas.

Honda had the CVCC which passed emission standards WITHOUT a catalytic converter. The standards changed. Funny how that happens, eh?

Several people have pointed out that diesels have more PPM of NOX or whatever than a Hummer. Less TOTAL, but it's the PPM (parts per million) that counts, not total emitted per mile. Fake example, but you'll get the idea. Let's say that car A emits X NOX over 1 mile. A Hummer emits 2X over the same mile, because it burns three times or more fuel. Less TOTAL emissions for the car, but the Hummer wins on percentage, not on total pollution.

Note that the regulations do not penalize the Hummer, but the vehicle that actually puts out less total pollution! This is real-world. Small cars mean small profits, both for the auto manufacturers and the oil producers.

Of course, this is the same world that *REWARDS* politicians for spending MORE money, instead of rewarding those who spend less. Starting to see the picture?
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Old 02-25-2008, 09:00 PM   #4
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Re: Big Picture. I wonder why auto manufacturers include remote starters as an added feature for those who live in cold climates, but don't include block heaters?
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Old 02-26-2008, 02:44 AM   #5
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Here is a good chart:


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Old 02-26-2008, 04:24 AM   #6
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That looks pretty much like the curves I was referring to above.
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Old 02-26-2008, 05:38 AM   #7
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Now I get it!

Thank you very much, for the explanation and that graph, I wen't to the Hurrican Horse Power site and printed the graph. Those descending and acending lines are what got me, I thought the HC and the NOX were straight lines, but the dip and peak really got me, it really answered so many questions.

I didn't know how the Nitrogen Oxide was produced, but now realizing that the 80% nitrogen in our atmosphere is the left over byproduct of the oxygen being stripped from it during combustion really opened my eyes.

Also the CAFE requirements are trying to get the NOX as low as possible reguardless of the fact that cars will get worse mpg, it is so very interesting.

Now the great conspiracy of the Hummer vs. the economy car makes sense. The auto industry is in the business to make money, the only thing that will make them change their tune would be people not buying SUV's because gas is so expensive, like last year when gas was getting near 4 dollars a gallon.

So on my future mpg machine I now plan on a Scan Gauge, EFIE, an air fuel ratio gauge, and a pyrometer.

Now here's another idea as far as smog and possible mpg experiments go. I plan on building an HHO generator, with the extra hydrogen making the O2 sensor read rich and lean the engine out, will the added O2 and hydro lower overall NOX? Also it would take a huge amount of build time, but constructing a Geet Pantone fuel super heater, making fuel a gas, I wonder how smog would be effected. The guys at Geet say 90% less emissions, but that's on a carburated vehicle. With the ECU, FI, O2 sensor controlled cars of today, what would come out of the tail pipe?

One reason this intrigues me is I saw the camera shot inside the cylinder of a Ford Taurus on its combustion cycle. With the injector aimed right at the intake port, I was amaised at how much unatomized fuel is squirted inside the chamber and how incomplete the burn is. From the old days of a propane carburator convesion, I wonder if there is a port injected propane update?

I'm forever trying to figure out how to make a car go 100 miles on an eye dropper of fuel.
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Old 02-26-2008, 05:50 AM   #8
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NOx happens when the combustion temperature is high, hot enough to burn the Nitrogen, it just so happens that the peak of that graph is the hottest combustion temperature. So water injection or other methods would cool the burn and limit NOx production.
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Old 02-26-2008, 09:17 AM   #9
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Quote:
Originally Posted by Scott View Post
I'm forever trying to figure out how to make a car go 100 miles on an eye dropper of fuel.
There's only so much energy in a gallon of gasoline.
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Old 02-28-2008, 12:04 AM   #10
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Quote:
Originally Posted by Scott View Post
Now until I discovered Gassavers, I thought fuel injection was the best that you can get. Then I learned about lean burn and low emissions. Coming from California, I grew up with the California versions of cars getting worse mileage and lower performance.
I'm not so sure that nitrogen is "burned" as much as NOx is a side reaction product of higher temperature combustion. NOx reacts with hydrocarbons to form smog. Smog annoys people in LA. Since they have juice and money the rest of us have to play along. For now.

One of the earliest ways to reduce NOx was the EGR valve. EGR, or "exhaust gas recirculation" took some of the engine exhaust and fed it back into the intake manifold. This was done to change the chemistry of the fuel air mixture, to change how the combustion process unfolded. The change caused a reaction shift away from NOx products. This also reduced the amount of energy in the mixture - since you were replacing air and fuel droplets with exhaust gases. Get a malfunctioning EGR valve and you'll soon know what I mean - stalls and other stuff.

Even the old Hondas, I think, had EGR valves.

Another way to reduce NOx is to use the energy in gasoline to reduce NOx back to nitrogen and oxygen.

Converters are touchy animals. They require just the right amount of gases at just the right time. Too lean and they do not work. Too rich and they super heat and the catalyst beds melt. Usually it's best to let the mixture cycle to allow for proper cooling.

If we did not need to feed the converter we'd have more energy to move us here and there. They are a net drain though properly fed and cared for they work well. The cycling also permits the use of cheap "switching" narrow band Oxygen sensors versus more expensive "wide band" sensors.

Another method to reduce NOx is to change the timing. I've read that the most efficient combustion occurs just short of "pre-detonation". However this is the same timing that causes a lot of NOx emissions.

So by changing the timing away from this area you get less NOx emissions, but you pay for it with a loss of power. So you have to push more gasoline into the engine for the same amount of power.


Honda CVCC technology does require a cat converter. Older Honda motors cannot pass emissions checks without a reasonably well maintained catalytic converter. My 1990 CRX failed two years ago because I did not have a fresh converter. Once I purchased one and properly installed it my checks went through easily.

Yeah, the standards "tightened". What else is new?

Gene
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