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Sludgy 03-23-2009 11:07 AM

WAI increases economy in O2 sensor/feedback fuel injected cars by reducing throttling losses at part load. EGR works the same way.

CAI hurts FE at part throttle, but it does improve power at full throttle.

Philip1 03-23-2009 11:47 AM

I have completed my experiment and here are the results HAI wins by .........10.1mpg See the link below.

https://www.gassavers.org/showthread.php?t=10415

Philip1 03-23-2009 03:10 PM

Quote:

Originally Posted by NovaResource (Post 130639)
Because trying something that you know won't work (and has been proven not to work by others) is a waste of time. If you would like to prove me wrong, be my guest.


Did you get a metal for that accomplishment? When you get to 100% over the EPA let me know. Until then, here's a cookie for you.

https://thehealthblogger.com/wp-conte.../07/cookie.jpg

Actually I do get metals and papers for doing this because I spend less money on fuel that means I get $$ in my pocket :p

Jay2TheRescue 03-23-2009 03:34 PM

$$ with which you can buy a box of cookies?

GasSavers_maximilian 03-23-2009 03:50 PM

But the cookies make you gain weight, which hurts your mpg...

theholycow 03-23-2009 03:54 PM

Cookies give you a sugar rush, which enables you to put more energy into hypermiling strategies that require lots of attention, like EOC.

GasSavers_NovaResource 03-24-2009 03:43 AM

Quote:

Originally Posted by philip1 (Post 130660)
I have completed my experiment and here are the results HAI wins by .........10.1mpg See the link below.

https://www.gassavers.org/showthread.php?t=10415

^^^ Total BS.

You test was not accurate. You drove less than 100 miles per test and the mileage wasn't even the same between the 2 tests. And it's way to easy to pump an extra half gallon when you only used 1.5 gallons.

Nice try but you FAIL.

Jay2TheRescue 03-24-2009 03:54 AM

When you're talking a distance like that, 4/10 of a mile is statistically insignifigant. He drove 130.8 miles. The same trip back to back. At our standard hypermiling speed of 55 MPH he would have spent a minimum of 2.38 hours on the road. Are you offering to set up your vehicle, drive in a 300 mile circle, one with, and one without HAI back to back? That's going to be one heck of a day driving 600 miles, at 55 MPH that's just shy of 11 hours on the road.

-Jay

R.I.D.E. 03-24-2009 04:21 AM

2 Attachment(s)
Quote:

Originally Posted by NovaResource (Post 130623)
The time a WAI will help fuel economy is in colder weather while the engine is warming up. But it's not because the engine is getting warm air instead of cold air, it's because the engine is getting up to operation temp quicker. Once the car is up to operating temp the WAI is no longer helping. The fuel savings is not from a WAI but from a engine that gets up to operating temp sooner. This is why test results show little improvement and vary greatly with different cars. A car that warms up quickly on it's own will show little improvement with a WAI but a car that takes a long time to warm up normally will show greater improvement with a WAI.

This is the reason why older carbureted cars of the 70's and 80's had factory installed, vacuum controlled warm air systems. When the engine was cold, a flap in the air cleaner lid closed to block the cold air inlet and pull air in off the outside of the exhaust manifolds. As the engine warmed the valve would open to allow in colder air and block of the hot air. Another reason for this is that carbureted engines don't atomize the fuel that well. The hotter air helped with fuel atomization however, this is not a problem in modern cars with fuel injection.

The flap operated whether the car was cold or warm. When it malfunctioned you could get killed trying to cross a street, the hesitation is something younger drivers have never experienced. Fuel mileage dropped 50%, plugs black.

It didn't work cold, because there was no heat to warm anything up The choke was used for that. Some cars had passageways that allowed hot exhaust gases to pass through the intake manifold (1937 Ford). The Chrysler slant sixes had a exhaust manifold junction right under the carburetor to warn things up.

Warm or cold----facts backed by real evidence.

Again, best fuel economy comes from a fully warmed up engine (warm coolant and warm oil), not warm intake air. You want a good idea for better economy? Install an intake system that pulls in warm air during startup when the engine is below operating temp but switches to cold air when the engine is fully warm. Another good idea: install an engine block heater and an oil pan heater to keep the coolant and oil temp warm when the engine is not running.

Lets see, by your statement you have concluded that there is no difference between a warm engine at 20 below and a warm engine at 100 degrees as far as fuel economy. I would like to see you provide a shred of proof of that statement, or are the temperature extremes too great.

The imperfections of modern fuel injection are clearly demonstrated by the efforts of manufacturers to achieve Homogenous Charge Compression Ignition in gasoline engines. Homogenous Charge means the fuel and air mixture is truly evenly distrubuted in the combustion chamber. That same mixture is ignited by compression alone without any spark whatsoever. The result is a 25% improvement in economy as well as the elimination of the catalytic converter with virtually zero regulated emissions.

Why would manufactirers spend tons of money to improve a system if your statement about it being perfect was true? The fact is the present systems look much better when compared to the old carburetor types, however there is still a massive potential for improvement.

Google HCCI if you really want to learn that there is much room for improvement over the present system that you describe as perfect. By perfect you imply that there is no room for improvement in fuel distribution because modern engines are fuel injected. HCCI proves without any doubt that modern systems are far from perfect.

The attached photo is my mileage from my trip yesterday. 65 MPG for 355.5 miles. Almost all of it was highway. The EPA highway rating for my car is 50 MPG. My modifications are a 40% grille block and 44 PSI air in the tires. Temperatures ranged from just above freezing to 65 degrees. Driving was from eastern Virginia to Blacksburg Virginia with elevation changes of 2000 feet. The grille block also retains heat in the engine compartment that increases the air temp to the intake system on the engine.

How much of the improvement was driving style, grille block, or tire pressure, or warm air would be difficult to distinguish, but the net overall improvement is 30%. Also consider that that is on 10% ethanol fuel which has a lower energy content than non ethanol fuel.

Also notice the fule guage is reading half a tank. That is a 10.5 gallon tank.

regards
gary

GasSavers_NovaResource 03-24-2009 04:25 AM

Quote:

Originally Posted by Jay2TheRescue (Post 130718)
When you're talking a distance like that, 4/10 of a mile is statistically insignifigant. He drove 130.8 miles. The same trip back to back. At our standard hypermiling speed of 55 MPH he would have spent a minimum of 2.38 hours on the road. Are you offering to set up your vehicle, drive in a 300 mile circle, one with, and one without HAI back to back? That's going to be one heck of a day driving 600 miles, at 55 MPH that's just shy of 11 hours on the road.

-Jay

Do you really believe that a WAI increases fuel economy by 10.1 mpg? Get real. If that was true, every car made today would have on from the factory. But they don't.

A SCIENTIFIC test needs to be done. Strick a car on a dyno, stabalize the coolant and oil temps, set a steady speed and maintain the same external air temps and use a scan guage to measure instand MPG and then switch from a external air inlet to an engine compartemt inlet and measure the difference.

GasSavers_NovaResource 03-24-2009 04:37 AM

Quote:

Originally Posted by R.I.D.E. (Post 130719)
Lets see, by your statement you have concluded that there is no difference between a warm engine at 20 below and a warm engine at 100 degrees as far as fuel economy. I would like to see you provide a shred of proof of that statement, or are the temperature extremes too great.

An engine at operating temperature (coolant and oil temps) will create the same MPH regardless of the intake air temps (within reason). Too hot and detonation will happen. That means, the engine coolant and oil are the same temps regardless of weather temps.

Quote:

Originally Posted by R.I.D.E. (Post 130719)
The imperfections of modern fuel injection are clearly demonstrated by the efforts of manufacturers to achieve Homogenous Charge Compression Ignition in gasoline engines. Homogenous Charge means the fuel and air mixture is truly evenly distrubuted in the combustion chamber. That same mixture is ignited by compression alone without any spark whatsoever. The result is a 25% improvement in economy as well as the elimination of the catalytic converter with virtually zero regulated emissions.

Why would manufactirers spend tons of money to improve a system if your statement about it being perfect was true? The fact is the present systems look much better when compared to the old carburetor types, however there is still a massive potential for improvement.

Google HCCI if you really want to learn that there is much room for improvement over the present system that you describe as perfect. By perfect you imply that there is no room for improvement in fuel distribution because modern engines are fuel injected. HCCI proves without any doubt that modern systems are far from perfect.

HCCI is TOTALLY different than an Otto-Cycle engine. HCCI is basically a gasoline-fueled diesel engine. The last thing you want in an Otto-Cycle engine is pre-ignition, but that's exactly what you what from an HCCI. Apples...oranges

Quote:

Originally Posted by R.I.D.E. (Post 130719)
The attached photo is my mileage from my trip yesterday. 65 MPG for 355.5 miles. Almost all of it was highway. The EPA highway rating for my car is 50 MPG. My modifications are a 40% grille block and 44 PSI air in the tires. Temperatures ranged from just above freezing to 65 degrees. Driving was from eastern Virginia to Blacksburg Virginia with elevation changes of 2000 feet. The grille block also retains heat in the engine compartment that increases the air temp to the intake system on the engine.

How much of the improvement was driving style, grille block, or tire pressure, or warm air would be difficult to distinguish, but the net overall improvement is 30%. Also consider that that is on 10% ethanol fuel which has a lower energy content than non ethanol fuel.

The grille block does 2 things. It maintains the engine coolant and oil temps but it also makes the car more aerodynamic by keeping air from entering the engine compartment. That along will make the car more fuel efficient. Like I said, if the engine temps are the same (20-deg or 100-deg) the engine should get similar fuel economy regardless of intake air temp.

GasSavers_maximilian 03-24-2009 05:13 AM

Quote:

Originally Posted by NovaResource (Post 130720)
Do you really believe that a WAI increases fuel economy my 10.1 mpg? Get real. If that was true, every car made today would have on from the factory. But they don't.

That's because you sacrifice max power to get that advantage. As I pointed out before, a much better approach if starting from scratch is to designate a smaller engine if you have power to spare.

GasSavers_maximilian 03-24-2009 05:23 AM

Quote:

Originally Posted by R.I.D.E. (Post 130719)
HCCI proves without any doubt that modern systems are far from perfect.

Careful you don't go too far with that (and I'm not implying you are). HCCI gains from increased compression ratios, not just improved combustion (yeah, yeah, and other stuff too like potentially lower throttling losses). Since the gains from increasing the standard compression ratios seen in normal spark ignition engines is pretty significant (the curve is still pretty steep at that point), this is probably most of it.

Jay2TheRescue 03-24-2009 05:25 AM

I'm saying that in that particular vehicle it works. 10 MPG is well beyond any conceivable margin of error for this test. I would agree that more testing needs to be done, but I don't buy the "Every car would have it already" argument. I can tell you that 2 of my 3 vehicles that I own have it setup from the factory. Manufacturers aren't solely concerned about mileage. They have to make sure the car passes emissions, and has good power. High HP numbers sell cars. WAI/HAI lowers these numbers. Yea, an affordable car can be made that gets great mileage, but if that was the only reason people bought cars was for high mileage numbers then everybody would either have a Geo Metro or Civic VX in their driveway. Do a search on the site. There are many others that claim to have positive results with WAI. For some reason Saturns do extremely well with WAI/HAI.

I'm just saying I wouldn't dismiss it so quickly.

GasSavers_maximilian 03-24-2009 05:26 AM

I can't disagree that a really well controlled series of tests would be great. That said, however, we can say something in the absence of them. Copied from the HAI experiment thread:

When there's uncertainty, I just use the following:

(chance of success)*(estimate of benefit) + (fun of trying)
vs
(cost & effort to try) + (chance of damage)*(estimated cost of damage)

In this case everything on the right hand side is very low. Since the chance of success is mixed, and some people are claiming a good sized benefit I think it's worth giving a shot. You may assign different values to these parameters than I do, and rightly so.

GasSavers_NovaResource 03-24-2009 06:59 AM

More good reading:
https://www.nextautos.com/auto-shows/...inject-engine/
Quote:

Mazda has announced its new lineup of direct-injection engines, called the DISI (direct injection spark ignition). The announcement of the performance enhancing, fuel conscious engines comes only weeks after Ford?s EcoBoost announcement.

The I-4 DISI engine seeks to achieve a 15-20 percent improvement in performance and a 20 percent increase in fuel economy over Mazda?s 2.0L engines.

According to the press release, the DISI engine will reduce energy loss and improve thermal efficiency with a variety of technological engineering. This includes cooling the air intake temperature and reshaping the combustion chamber.

Mazda also noted that they are looking to produce direct-injection diesel turbo engine technology that can improve the fuel economy and emissions by 10 percent as well.
https://www.passagemaker-digital.com/.../200903/?pg=81
Quote:

Related to air filter performance is the temparature of the air being consumed by the engine. Warm air is thinner or less dense than cool air, and thinner air burns less efficiently. Therefore, it is desirable to keep the air inlet temperature to a minimum.

bobc455 03-24-2009 09:04 AM

Quote:

Originally Posted by NovaResource (Post 130720)
A SCIENTIFIC test needs to be done. Strick a car on a dyno, stabalize the coolant and oil temps, set a steady speed and maintain the same external air temps and use a scan guage to measure instand MPG and then switch from a external air inlet to an engine compartemt inlet and measure the difference.

An A-B-A-B test would be sufficiently demonstrative - under condition "A" (i.e. cold air) you get a certain result, then you modify it to condition "B" (warm air) and you get a different result, then return the car to its unmodified condition "A" and ensure that the result returns to its previous value.

-BC

GasSavers_NovaResource 03-24-2009 09:11 AM

Quote:

Originally Posted by bobc455 (Post 130802)
An A-B-A-B test would be sufficiently demonstrative - under condition "A" (i.e. cold air) you get a certain result, then you modify it to condition "B" (warm air) and you get a different result, then return the car to its unmodified condition "A" and ensure that the result returns to its previous value.

-BC

I 100% agree.

And I love the thread you have in you signature about doing a SCIENTIFIC experiment: https://www.gassavers.org/showthread.php?t=2

R.I.D.E. 03-24-2009 10:13 AM

Warm air allows larger throttle openings and higher effective compression.

Warm air also allows less fuel to be injected for the same mass of air consumed.

Fuel delivery systems add fuel based on temperature as well as mass.

The power delivered by any engine is a direct function of the EFFECTIVE compression. Put a vacuum guage on your engine, keep the revs low, in the 1500 to 2500 range in the highest gear the vehicle can handle. Accelerate with the highest load, lowest revs, and lowest vacuum, without applying enough throttle to get into full load enrichment.

Voila, the secret to the pulse portion of hypermiling.

The concept that making a vehicle more powerful is basically flawed, when you are talking about an economy strategy. This is clearly demonstrated by the difference in mileage between a Civic SI and a Civic VX.

Understand "effective compression". All engines create power utilizing the difference between compression pressure and combustion pressure. The highest effective compression (lowest vacuum reading) is the highest effective combustion pressure for any given mass of fuel delivered.

Take a 2.5 liter 4 cylinder engine on a dyno. Put a 20 HP load of the engine. Measure the fuel consumption at 1700 RPM. Then place a 50 HP load at the same speed and you get 30 more hp, for half the fuel it takes to get the first 20 HP. That is due to effective compression being maximized.

If you have any manifold vacuum you are proportionately reducing the effective compression, as well as efficiency.

Diesels solve the problem by elimination of the throttle butterfly.


regards
gary

GasSavers_maximilian 03-24-2009 10:40 AM

There's more than throttling losses at partial load. Frictional losses don' t decline quickly with load, so they become a greater proportion as it decreases. This diminishes economy. Diesels suffer from this too. Variable compression can help get around this, but is a much more complicated mechanism.

R.I.D.E. 03-24-2009 01:06 PM

I can name at least 10 different sources of losses.

regards
gary

GasSavers_maximilian 03-24-2009 01:25 PM

I just wanted to make sure people were aware that there's a lot going on to make big engine's bad. I didn't mean to nitpick.

R.I.D.E. 03-24-2009 01:41 PM

A good read is to look at what Honda did to make the VX the non hybrid mileage champ of the Honda line from 92-95.

I actually have design for a valveless variable compression rotary piston engine. It has an additional capability of destroking itself completely and storing energy in its own spinning mass as a flywheel.

Combined with an Infinitely Variable, in wheel transmission at each wheel. it provides a potentially game changing powertrain configuration.

regards
gary

GasSavers_maximilian 03-24-2009 01:47 PM

I am doing engine design work as well, but can't talk about it. IP issues suck. Be careful.


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