Alcohol in gas affects mixture

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You cannot take the 15%(in your example) ethanol out of the 1 part fuel, just because you don't think it will burn good enough. And then use that as an example of how it changed the a/f ratio. Like it or not it's there and is a fuel regardles of the burn rate, BTU output or anything and will need to be counted as part of the a/f ratio. So there is where your math is flawed. Period.

The problem is a gasoline motor just doesn't have the compression to get all the power out of the ethanol. You can ignore it all you want but physics don't lie. It's not going to burn completely in a gas motor period.

In thoery you could be looking at incomplete cumbustion, in practice it's actually works better than you think.

No it doesn't, in practice it happens just as the "thoery" (aka the cold hard facts) perdict.

They don't run worse when on e85. I know of too many people choossing to run e85 even in heavy Suburbans because they run better. Really the stoich ratio doesn't matter at all for the op issue. NO vehicle runs stoich when accelerating. The e85 guys aren't running anywhere near 6.4:1 and that is when they are making power, cruising is above 12:1.

Cruising is above 12:1 is for gasoline, not E85, you are getting your math mixed up here. More of these mystery people who know how to bend physics.

Fuel ........................ AFRst ........ FARst ....... Equivalence Ratio ... Lambda
Gas stoich ................ 14.7 .......... 0.068 ................ 1 ................... 1
Gas max power rich .... 12.5 .......... 0.08 ................. 1.176 .............. 0.8503
Gas max power lean .... 13.23 ........ 0.0755 .............. 1.111 ............. 0.900
E85 stoich .................. 9.765 ....... 0.10235 ............ 1 ................... 1
E85 max power rich ...... 6.975 ....... 0.1434 .............. 1.40 ............... 0.7143
E85 max power lean ..... 8.4687 ...... 0.118 ............... 1.153 .............. 0.8673
E100 stoich ................ 9.0078 ...... 0.111 ............... 1 .................... 1
E100 max power rich .... 6.429 ........ 0.155 .............. 1.4 .................. 0.714
E100 max power lean .... 7.8 .... ...... 0.128 .............. 1.15 ................ 0.870

Again you can't be breaking the law of physics unless you have a magic engine that you used some Harry Potter spell on.

No, it's just cheaper for them to use theoretical math to post a number that no agency is checking. Independent test have shown mpg loss in the single digit percentages, not the 30% they post.

There are independent tests that have shown about a 30% drop in MPGs with E85. Like this one that took me a second to find.

This chart shows how our 2007 Chevrolet Tahoe performed while running on E85 and gasoline in three fuel-economy tests and overall, in four acceleration tests, and in three emissions tests for gasoline vehicles.E85 vs GASOLINE*


Fuel economy, mpg
City 7 9
Highway 15 21
150-mile trip 13 18
Overall 10 14
Acceleration
0-30 mph, sec. 3.4 3.5
0-60 mph, sec. 8.9 9.1
45-65 mph, sec. 5.7 5.8
Quarter-mile, sec./mph 16.8/84.6 16.9/84.5
Emissions, parts per million
Nitrogen oxide 1 9
Hydrocarbons 1 1
Carbon monoxide 0 0 http://www.consumerreports.org/cro/2011/01/the-great-ethanol-debate/index.htm

Here is another one, but it reports a drop in MPGs of only 26%. http://www.edmunds.com/fuel-economy/e85-vs-gasoline-comparison-test.html


No, because there would be cold climate issues with e98(highest you will find). The e85 is a good trade off and is still reduced to e70 in some places as cold weather nears. There is also nothing to be gained performance wise from anything much stronger than e85. Sounds like prejudice against farmers. If you produced something that all of a sudden had two use from the same exact product wouldn't you feel it was worth more. However none of the money will ever get back to the individual farmer. Besides ethanol doesn't just come from corn.

Another con of E fuels that even you have admitted, poor cold start properties. Stronger than E85 means you can run even more compression with less spark knock therefore more power, so there is still a gain with the cost of hard starting. Old kerosene engines still had to be started on gasoline, even some early diesels had to be started on gas. I don't have a prejudice against farmers, I have a prejudice against people trying to screw more money out of me while giving me less return. A very poor try at a Ad hominem. It is only worth more due to more customers for that product, and farmers can cut back corn production to keep prices high. Ethanol also comes from sugercane which we don't grow too much of in the US.


You can't be more wrong here. There is nothing optimized for ethanol use in my combo yet with the mix I'm running i've lost zero power and will got to a higher ratio soon. There has been some people that have switched to E85 and didn't pick up any time or very little. But I haven't heard of any other than Chris that has lost time. There is also the advantage to running cooler. It would help to be consistant for a bracket car, even one that isn't going for all out power. To take full advantage of it yes, higher compression would be good. Plenty of people pay higher prices for 93 or even 100 octane fuel, or even race fuel. Being able to run the same car on fuel that cost less than 87 is great. Why would you be against that.

You or anyone else can disagree with me all you want, but i'm actually using it, and will post any and all results. Regardless, i really think it's here to stay, so you might want to look at how to make good use of it.

Just heresay here, no proof, no science, no math, or facts, or any form of proof for your magic combo that breaks the law of physics. What you have stated is impossibe without more compression and other major mods. I have stated and explained to you many times already of what and why you are saying is bogus. E10 is a leaner fuel for a gasoline motor, and must be retuned to a richer mixture and less timing advance to avoid spark knocking. Higher octane fuels burns at a lower rate so you can run more compression. But if you have a lower compression engine they you will get zero gains from higher octane fuels, and even see a slight power loss and MPG loss due to a more incomplete burn, same thing happens with Ethanol blends in a lower compression gasoline motor, only worse. E85 is about 93 octane, but you have to use more of it that defeats any price savings . As far as octane is concerned, it is a measure of a fuel's resistance to detonate!! It isn't affected by what the "gasoline" is composed of. The fuel MIXUTRE, which may contain whatever the oil companies put in it has to pass their testing for the certain octane rating and thats why they rate it as so. Regardless of what is in this MIXTURE of gasoline, if the fuel is rated at a certain octane it should/better resist detonation like any other fuel mixture that is rated at the equivalent octane. However since it is a leaner fuel you have to run a richer mix to avoid spark knock despite the octane rating. It is a widespread but misguided belief that if you use a high octane fuel your car's performance will automatically increase. You won't achieve any improved performance from using higher octane fuels unless your vehicle's engine is designed for them, ie higher compression. Ethanol needs a richer mixture and higher compression to match gasoline output, no ifs, ands, or buts about it. Our 1980s era cars have even lower compression than most modern stuff and thus run even poorer on Ethanol blends. You might as well state the Earth is flat and at the center of the universe, it's just as correct.
 
Clone TIE Pilot said:
You cannot take the 15%(in your example) ethanol out of the 1 part fuel, just because you don't think it will burn good enough. And then use that as an example of how it changed the a/f ratio. Like it or not it's there and is a fuel regardles of the burn rate, BTU output or anything and will need to be counted as part of the a/f ratio. So there is where your math is flawed. Period.

The problem is a gasoline motor just doesn't have the compression to get all the power out of the ethanol. You can ignore it all you want but physics don't lie. It's not going to burn completely in a gas motor period.

It still doesn't mean you can just delete it from the a/f ratio and say that it leans it out.

In thoery you could be looking at incomplete cumbustion, in practice it's actually works better than you think.

No it doesn't, in practice it happens just as the "thoery" (aka the cold hard facts) perdict.

Sure, because you say so right. How much testing have you personally done again?

They don't run worse when on e85. I know of too many people choossing to run e85 even in heavy Suburbans because they run better. Really the stoich ratio doesn't matter at all for the op issue. NO vehicle runs stoich when accelerating. The e85 guys aren't running anywhere near 6.4:1 and that is when they are making power, cruising is above 12:1.

Cruising is above 12:1 is for gasoline, not E85, you are getting your math mixed up here. More of these mystery people who know how to bend physics.

Fuel ........................ AFRst ........ FARst ....... Equivalence Ratio ... Lambda
Gas stoich ................ 14.7 .......... 0.068 ................ 1 ................... 1
Gas max power rich .... 12.5 .......... 0.08 ................. 1.176 .............. 0.8503
Gas max power lean .... 13.23 ........ 0.0755 .............. 1.111 ............. 0.900
E85 stoich .................. 9.765 ....... 0.10235 ............ 1 ................... 1
E85 max power rich ...... 6.975 ....... 0.1434 .............. 1.40 ............... 0.7143
E85 max power lean ..... 8.4687 ...... 0.118 ............... 1.153 .............. 0.8673
E100 stoich ................ 9.0078 ...... 0.111 ............... 1 .................... 1
E100 max power rich .... 6.429 ........ 0.155 .............. 1.4 .................. 0.714
E100 max power lean .... 7.8 .... ...... 0.128 .............. 1.15 ................ 0.870

Again you can't be breaking the law of physics unless you have a magic engine that you used some Harry Potter spell on.

Like it or not, i'm telling you what these guys are running. If you read any of the papers that are posted above you will see where it say the loss in mpg will be reduced when you add compression to optimize use. That's what these guys are doing so they aren't losing near as much, so their a/f mixtures are a lot leaner than you'd think.

No, it's just cheaper for them to use theoretical math to post a number that no agency is checking. Independent test have shown mpg loss in the single digit percentages, not the 30% they post.

There are independent tests that have shown about a 30% drop in MPGs with E85. Like this one that took me a second to find.

This chart shows how our 2007 Chevrolet Tahoe performed while running on E85 and gasoline in three fuel-economy tests and overall, in four acceleration tests, and in three emissions tests for gasoline vehicles.E85 vs GASOLINE*


Fuel economy, mpg
City 7 9
Highway 15 21
150-mile trip 13 18
Overall 10 14
Acceleration
0-30 mph, sec. 3.4 3.5
0-60 mph, sec. 8.9 9.1
45-65 mph, sec. 5.7 5.8
Quarter-mile, sec./mph 16.8/84.6 16.9/84.5
Emissions, parts per million
Nitrogen oxide 1 9
Hydrocarbons 1 1
Carbon monoxide 0 0 http://www.consumerreports.org/cro/2011/01/the-great-ethanol-debate/index.htm

Here is another one, but it reports a drop in MPGs of only 26%. http://www.edmunds.com/fuel-economy/e85-vs-gasoline-comparison-test.html

Nice and up to date huh? You know we could go back and forth posting very different results all day. I just wanted to point out that people are having very different results. Results that you say are impossible.


No, because there would be cold climate issues with e98(highest you will find). The e85 is a good trade off and is still reduced to e70 in some places as cold weather nears. There is also nothing to be gained performance wise from anything much stronger than e85. Sounds like prejudice against farmers. If you produced something that all of a sudden had two use from the same exact product wouldn't you feel it was worth more. However none of the money will ever get back to the individual farmer. Besides ethanol doesn't just come from corn.

Another con of E fuels that even you have admitted, poor cold start properties. Stronger than E85 means you can run even more compression with less spark knock therefore more power, so there is still a gain with the cost of hard starting. Old kerosene engines still had to be started on gasoline, even some early diesels had to be started on gas. I don't have a prejudice against farmers, I have a prejudice against people trying to screw more money out of me while giving me less return. A very poor try at a Ad hominem. It is only worth more due to more customers for that product, and farmers can cut back corn production to keep prices high. Ethanol also comes from sugercane which we don't grow too much of in the US.

I never said there wasn't cons to it, but mixing with gas helps to prevent that. That's why most stations in cold climate areas will drop back to e70. The only time that matters is if your pushing the limits with e85, it could be bad to not knowingly add e70. Ethanol is/can be produced form a lot more products than that. One of which is saw grass or switch grass. It will grow almost anywhere and quickly. I will drop this just because it borders on a political argument.


You can't be more wrong here. There is nothing optimized for ethanol use in my combo yet with the mix I'm running i've lost zero power and will got to a higher ratio soon. There has been some people that have switched to E85 and didn't pick up any time or very little. But I haven't heard of any other than Chris that has lost time. There is also the advantage to running cooler. It would help to be consistant for a bracket car, even one that isn't going for all out power. To take full advantage of it yes, higher compression would be good. Plenty of people pay higher prices for 93 or even 100 octane fuel, or even race fuel. Being able to run the same car on fuel that cost less than 87 is great. Why would you be against that.

You or anyone else can disagree with me all you want, but i'm actually using it, and will post any and all results. Regardless, i really think it's here to stay, so you might want to look at how to make good use of it.

Just heresay here, no proof, no science, no math, or facts, or any form of proof for your magic combo that breaks the law of physics. What you have stated is impossibe without more compression and other major mods. I have stated and explained to you many times already of what and why you are saying is bogus. E10 is a leaner fuel for a gasoline motor, and must be retuned to a richer mixture and less timing advance to avoid spark knocking. Higher octane fuels burns at a lower rate so you can run more compression. But if you have a lower compression engine they you will get zero gains from higher octane fuels, and even see a slight power loss and MPG loss due to a more incomplete burn, same thing happens with Ethanol blends in a lower compression gasoline motor, only worse. E85 is about 93 octane, but you have to use more of it that defeats any price savings . As far as octane is concerned, it is a measure of a fuel's resistance to detonate!! It isn't affected by what the "gasoline" is composed of. The fuel MIXUTRE, which may contain whatever the oil companies put in it has to pass their testing for the certain octane rating and thats why they rate it as so. Regardless of what is in this MIXTURE of gasoline, if the fuel is rated at a certain octane it should/better resist detonation like any other fuel mixture that is rated at the equivalent octane. However since it is a leaner fuel you have to run a richer mix to avoid spark knock despite the octane rating. It is a widespread but misguided belief that if you use a high octane fuel your car's performance will automatically increase. You won't achieve any improved performance from using higher octane fuels unless your vehicle's engine is designed for them, ie higher compression. Ethanol needs a richer mixture and higher compression to match gasoline output, no ifs, ands, or buts about it. Our 1980s era cars have even lower compression than most modern stuff and thus run even poorer on Ethanol blends. You might as well state the Earth is flat and at the center of the universe, it's just as correct.

For once the second half of this paragraph I agree with. I've already stated you need more fuel to make the same power with e85(but not because it's lean, it just doesn't contain the same energy), E10 the increase would be minimal at best and the decreased output with no increase in fuel would be negligible. It certainly wouldn't make it knock, which is where this all started. The problem is there is more to ethanol than just increased knock resistance. If you don't believe what my car does, come on over, i'll show anyone that wants to see. I'll even drain the tank and run on whatever mix you want. This is from one of the papers cited above.

• At substantially similar engine conditions, thermal
efficiency and engine power both increase with increasing
ethanol content, even when none of the fuels are knocklimited. Contributing factors to the higher power are a charge
cooling effect and a higher energy content of a stoichiometric
mixture per unit mass of air, which together, account for
more than 50% of the increased power. Contributing factors
to the increased efficiency are explored and include a mole
multiplier effect and differences in γ. The mechanisms and
the relative contributions of these efficiency effects are
currently being studied.
 
Sadly another typical discussion about pro/cons of Ethanol....

always a politically charged back and forth about "science" and real world results.
 
CWPottenger said:
Sadly another typical discussion about pro/cons of Ethanol....

always a politically charged back and forth about "science" and real world results.

Regardless of what side your on, it always seems to end the same.
 
This thread took a wrong turn at Albuquerque!
The op bonnewagon said a jet change made his car run better with e10 and he believed solved his detonation problem.
The only way to tell if that's true is to do side by side in his 301 with straight gas and e10 with both tunes rich and lean
on same day/temp/humidity
jrm81 I think comparing your supercharged 350 to his low compression smog 301 is not a comparison
your motor obviously runs great with e10.
😀
 
79wagonator said:
This thread took a wrong turn at Albuquerque!
The op bonnewagon said a jet change made his car run better with e10 and he believed solved his detonation problem.
The only way to tell if that's true is to do side by side in his 301 with straight gas and e10 with both tunes rich and lean
on same day/temp/humidity
jrm81 I think comparing your supercharged 350 to his low compression smog 301 is not a comparison
your motor obviously runs great with e10.
😀

You might be surprised. At best i'm sitting at 8.5:1 compression. There's no boost when cruising, and I have aluminum heads. It's a stock smog era bottom end.
 
79wagonator said:
This thread took a wrong turn at Albuquerque!
The op bonnewagon said a jet change made his car run better with e10 and he believed solved his detonation problem.
The only way to tell if that's true is to do side by side in his 301 with straight gas and e10 with both tunes rich and lean
on same day/temp/humidity
jrm81 I think comparing your supercharged 350 to his low compression smog 301 is not a comparison
your motor obviously runs great with e10.
😀

Tell me about it. E10 is a leaner fuel for a gasoline designed engine, and adjusting the A/F mixture richer is a band aid that makes the motor drivable with the cost of lower MPGs and power because of the lower than ideal CR for ethanol. The OP had to change the tune from the optimum tune for his engine to a compromise A/F mix ratio between Gasoline and ethanol. Why jrm81 keeps stating that a gasoline motor will run just fine on E10 without any changes what so ever is beyond me since the OP disproved this. I didn't know jrm81's motor was supercharged since this changes the story quite a bit. Besides being able to run higher compression in a n/a motor on ethanol, you can also run higher boost levels with a forced induction motor on ethanol and regain the efficiency from the richer a/f mixture. One can't simply adjust compression on a n/a motor without taking it apart, but one can adjust boost on a forced induction motor without taking things apart. So this indeed is a bad comparison. One I was not aware of until now which makes his arguments all the weaker. If his motor was only n/a, it would not be running as well as it does but again a super charger is a major mod to a engine, an emissions illegal one but that is another can of worms. If he had stated this earlier in the thread we could have prevent alot of this mess and confusion

Also jrm81's motor isn't a stock motor since it has a supercharger, no G bodies came supercharged, which goes against his claim of a stock motor. Also G bodies never came with aluminum heads which are less prone to spark knock than the stock iron heads that G body V8s came with. It is why you can run more compression or boost with aluminum heads over iron heads. So while he may not have intended for these mods to optimize his motor for ethanol, they infact do so despite his claims otherwise. Boost can be a substitute for compression as is the case with jrm81's motor. So despite what he claims, he motor is optimized for ethanol more than the OP's stock motor. However a stock 70s 301 doesn't have a supercharger, boost, compression, or aluminum heads to help regain the lost efficiency due to having to enrich the mixture with E10 to avoid lean knock. To use more fuel just to make the same power without knocking isn't a good thing. While jrm81 can increase his boost to make up for his low CR and optimize his motor for E85. If his system can last not being eaten away is a different story.

There's no boost when cruising, and I have aluminum heads.

Those aluminum heads are masking a lean condition at cruise, just because you don't hear knocking doesn't mean it isn't happening at all. BTW they do sell E100 in Brazil since the late 1970s for neat ethanol vehicles there. They sell Honda Civics and other cars there that run on E100 with a fuel warming system for cold starting, older cars have a secondary reservoir gasoline tank for cold starts. Another statement from you proved false.
 
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