Would running lean save fuel?
 

I know that an air fuel ratio of 14.7:1 is in stoichiomitry, obviously running rich burns more fuel, and running lean reduces performance. But what if a car ran at 15.5 or 16:1 air to fuel ratio at all times, except when cold, under heavy load or at full throttle? I would think it would get better mileage, at the cost of worse throttle response and higher temps. Why is the air to fuel ratio so rich while cruising? Could the engine not do the same amount of work with a leaner air to fuel ratio, or would fuel consumption increase? Thanks, this always confused me.

Law and emissions

This is where your EGR helps...lets you run less air and fuel without having to change your AFR.

I tuned the carburetor on my gasoline powered suburban with the aid of my AEM wide band O2 meter for lean burn and it made about a 20% improvement over a properly tuned carb.
It works.

You do not want lean burn at high load, I burned all the exhaust valves on a fuel injected engine because I didn't know how to make it run rich at high load.

Makes you wonder if having your car make a little more NOx but reducing fuel use 20% might reduce overall emissions since your taking a chunk out of the 300 grams of NOx per gallon the refinery makes?

That matches my thought process. Not sure how much NOx a car in lean burn mode would produce. But 20% less fuel use should make up for that in my eyes especially if what your saying about NOx the refinery makes is accurate.

Where I live we do not have a NOx problem.
It's flat as far as you can see and one of the windest places in the united states.

Unfortunately EPA only cares about vehicle tail pipe.
I had no idea the refinery made 300gm of NOx per gallon.
Heck it's almost like the government is intentionally making the problem worse.

I have been around oil refineries and they do smell like NOx, but I didn't even think it was possible to release that much.

That sounds extremely high. Do You have a source for this?

If you do this on a 25-year-old car in USA then I'm pretty sure you're in the clear when it comes to emissions regulations.

Anyone who thinks the government produces regulations to help the average person is crazy. Maybe 100 years ago. The regulations are written by lobbies and special interest groups to carve out an advantage for themselves. Who benefits from using more gas and adding expensive parts to cars? In the name of reducing NOx which supposedly helps the common man. Must be nice every time the common man gets "helped" a CEO makes another billion.

The government is the biggest joke around. People are to easily bought and a man's word don't mean anything there. A man's word don't mean much anymore anywhere due to the fact we are showed by our leadership that it's ok to lie and hide things. Seems everyone has an ulterior motive. That's why technologies to improve gas milage have been bought out and buried since the beginning of the internal combustion engine.

I find it unlikely that the number is 300g. Seems slightly stretched but I have no doubt the truth of the matter would be shocking to many. 100+ undoubtedly. Have issues getting to read afr with torque on my car. I assume I don't have proper sensors for it. But seems even most diesel only produce less than 1g per mile. Trying to find some definitive tests though. On vacation so hope to come back on and find someone else did it. But respectively would guess that lean burn mode increase is typically 20%+ efficiency gain. If no emissions don't Increase by a matching rate someone should crack that aftermarket tuning/modding and make millions screwing over our governments for their Idiocracy.

If you have a carburetor vehicle all you need is a wide band O2 meter and the proper tuning kit for your carb.

For those concerned about the thermal stress that an engine would have while running leaner, and those who eventually would feel quite uncomfortable due to the increase on NOx, supplemental water injection might be a good way to overcome those issues.


Not just the refinery, since that extra amount of fuel (and the imported petroleum) would still require hauling, which is also quite energy-expensive and polluting. Considering that tanker ships hauling oil from the Middle East and Venezuela are not so strictly emissions-controlled as road vehicles, and that one of the main complains about NOx is that it turns sea water more acidic, lean-burn doesn't seem so problematic at all.

Check out my thread I just posted. goes into detail how Tackled the problem

http://ecomodder.com/forum/showthrea...tml#post545865