This explains it better:


Hense more power, more consumption.... with less dependence on atmospheric air due to quench = 5:1-6:1

EVERYONE?????

Seriously, those go hand in hand!!

I don't think anyone in quest of "more power" is going to comment or worry about fuel economy... :rotf:

what about "efficiency" horsepower?

ie putting a more efficient intake on so that power is not wasted drawing air into the engine, or putting an exhaust system on so that power is not wasted pushing exhaust gases out? there is plenty of stuff you can do to make more power and more economy.

I see tons of people commenting and worrying about fuel economy. shall I search threads?;)

The simple fact is, horsepower is made by more efficiently being able to add more fuel and more air.... simple as that. You can't make more power with less of either even in the most optimum environments.

:no: :rolleyes:


:D

the efficiency gains come from converting parts from restrictive oem parts to more "optomized" aftermarket parts. do you think your car came from the factory with the "optimum environment" for making perfectly efficient horsepower? no, they wanted it to be quieter, and nicer to drive than an F1 car.

I'm just sayin.

when I had my 350z stock I got like 25 mpg ont he highway. after I put my intake, plenum, and exhaust on it, I was getting over 30. granted, at WOT, I'm sure that my economy was worse than stock, but cruising, the system was much more efficient. do you think the EPA is computing mileage at WOT or cruising speeds?

Direct Injection more efficiently adds fuel to the combustion chamber by atomization.

Turbo's assist in forcing more atmospheric air into the cylinder so that more fuel can be added as well for more power

NO2 changes the atmospheric air properties so that the air is denser so that more fuel can be added, or added in conjunction.

If you want more power, you must have more fuel, simple as that. All the bolt on crap just assists in making the delivery more efficient. Once the optimum efficiency is hit, there is nothing else but more fuel and air.

Ethynol does not burn correctly in gasoline engines. It, like most other alcohol fuels need a compression ratio over 11.5:1 just to combust. My uncle's been running Hartog Oil for years, and according to him, ethynol is added to gasoline simply as a filler. That's why it's up to the particular station. It makes that 35,000 gallon tank underground "up to 10%" cheaper for them to fill back up, even though most of them don't pass on their savings to their customers. Then you get worse gas mileage and have to come back sooner.

While we're on the subject of gas/gas stations; did you know there's a return line at the handle of the hose that is there to return "fumes" back to the storage tank? When you click the hose to spray the fastest, fumes and spatter get returned through that. Too bad the flow sensor is before that, so you end up paying for a bit of fuel that ends up getting returned. Also, never fill up right after a station refills it's storage tank. When the refill, alot of crap that's settled to the bottom over the last few weeks gets stirred up. I wouldn't want to run that shit through my motor. Takes about a day and a half for it to settle back down. Just some fyi.

ok you've just said exactly what I did. congrats. we're now on the same page.

I'll set up survailance cameras at my gas station to see exactly when the trucks drop the new load in there.

lets get back on topic, shall we?

bottom line:
1. we're using the SAME amount of fuel and air
2. the fuel is slightly different

how is it possible that, given the same amount of fuel and air are going into the combustion chamber and no tuning has been performed, an engine can have more power and less economy?

You can ask the guy inside what their refill schedule is. It's usually consistant (every other wednesay, every 20 days, ect...).

yeah you beat me to it...... I understand what you're saying, it's just typically if you want allot more power.... you're finding ways to get more fuel and air in the system....

Making power is counter to efficiency... otherwise we would all have 1000HP, 100mpg cars....

to me it is fairly straight forward that if the new fuel creates more energy when burned, economy and power will go up. if it creates less energy when burned, both will go down.

we aren't talking about MORE fuel here though, we're talking about DIFFERENT fuel.

Agreed, but since Ethanol burns at 5-6:1 instead of 13-14:1.... efficiency is directly related.... and hence our side argument on more power=larger consumption of fuel.

to consume more fuel, you'd have to either be on the gas more, or have a different tune though. what am I not getting here?

Well you don't make horsepower at idle.....

ok here is what I am not getting:

more power = more horsepower at WOT. this is straight forward. it means that when you add ethanol to gasoline, you get a more explosive burn, releasing more energy and pushing the piston down harder for each power stroke.

less efficiency = more fuel needed to cruise. if each explosion is pushing the piston down harder on each power stroke, then you shouldn't need the same volume of fuel to create the amount of power needed to make your car go, say 55 mph. that means you're using LESS fuel to make it go 55 mph. that means you're actually running MORE efficiently.

But you are comparing two different fuel sources...

OH MY GOD

I want to ban you from my thread.

different fuel sources don't matter. the physics are the same dude. do you think that just because this other stuff is made from corn that it's magical and not subject to the laws of physics?

LOL!!!

Okay.... each explosion with ethanol does create a higher level of energy = more power.

But, since ethanol's squelch is at 6:1 instead of 14:1, it takes twice as much ethanol for each explosion as would gasoline.... so you get poorer gas mileage.


As compared to running 100% gasoline....

ok so what is making your car pump more fuel into the combustion chamber? to get worse gas mileage, you're going to have to either have a poorer burn, or tell your car to pump more fuel. there are two ways to pump more fuel: add more air, or change the way the computer is mixing. I don't think using 10% ethanol is changing either of these.

ut oh wheels are turning....

I wonder if, since ethanol is a "cleaner burning" fuel that the o2 sensor is not picking up the mixture as rich enough and adding more fuel to compensate.... that would mean that our cars would be running even more pig rich than normal... what do you guys think? this is the only thing that would make me believe the more power worse economy argument, and it actually makes sense... there is more fuel that the computer is seeing.... kinda. anyone?

I could find the equations later, but the thermal efficiency is directly related to the compression ratio of an engine. The fuel source matters not, its all just heat in as far as the energy is concerned. Its another reason why Diesels are more efficent than gasoline engines.

Ethanol CAN make more power in an engine if the compression ratio is raised to take advantage of it. Even if the engine is desiged for it though you are still going to have to burn more of it to get the same heat out of it due to the reduced energy content. There are numbers floating around, but running 100% Ethanol in an engine designed for gasoline WILL result in a gas mileage reduction of ~30%, I think running ethanol in an engine with a proper compression ratio will result in a reduction of ~5-10%. This is because while you are using more fuel to generate the heat, you are also becoming more thermally efficient. The gains in thermal efficiciency never offset the loss of energy per unit volume when compared to gasoline.

FYI, an engine is most "efficent" when it is running WOT at its torque peak (peak volumetric efficiency). The reason that this is not practical in real life is because it doesnt take into effect wind resistance. The faster you go the more energy you lose to drag. You can play some interesting games with CVTs, and engines that switch on and off to take advantage of this.

e-85 is hillbilly race-gas equivilent to 100+ octane. With a higher octane rating, you can run more boost and more time with better cooling and less knock. Modern cars run much hotter than necessary for emissions purposes. Alky injection not only bumps up the octane, but cools the cylinder with the water instead of fuel.

Less fuel=more power.

What we're all missing from this discussion is that the stoich for ethanol is NOT the same as gasoline. Gasoline is 14.7:1 while pure ethanol is 9:1.

That means that if you're burning pure ethanol your combustion is happening with 9 parts air and 1 part ethanol. That means that you're using more ethanol for the same amount of air than if it was pure gasoline just to have the combustion happen at stoich.

Now, if you add 10% ethanol to gas, you end up with a stoich of about 14.2 ... so if you guys using 10% ethanol-enhanced gas see your AFR's at 14.2 or so, you now know why. :D

Actually you are incorrect, i see a stoch of 14.6 or 14.7 with 10% Ethanol in my fuel at idle. Theory wise, that sounds logical... reality, it's not. Gasoline still supercedes as 90%. 10% alcohol isnt going to change a thing, except make your fuel burn quicker... which is something we are seeing here in CA and probably across the US. They ( oil companies ) are using it as a cheap filler and making even more money off conserving 10% of extra gasoline.

That's odd, because I see 14.1/14.2 with 10% ethanol and others have said the same thing that use the same Sunoco 94 gas up here.

Plus if you do the math it makes perfect sense.

I may put in 91 non-ethanol (can't get any higher on pure gas) just to see though.