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leveymg

(36,418 posts)
34. As a practical matter, gas engines rarely run more than 15 pounds boost (1.0 bar) on the street
Thu Sep 19, 2013, 08:02 PM
Sep 2013

Last edited Fri Sep 20, 2013, 09:33 AM - Edit history (1)

while Indy series alcohol engines are limited to 1.5 bars. By comparison, modern high-performance diesels routinely pull 30 peak pounds (2.0 bar.) Part of the reason that diesels can pull more boost is that diesel fuel contains 11% more energy than gas and diesel engines generally favor torque production and have much longer strokes and heavier reciprocating components with resulting lower rpms (and horsepower potential) than a similar boosted gasoline engine. Alcohol by comparison has 33% less energy potential than gasoline, so I would think an an alcohol fueled engine that operates at 2 bars plus to compensate for the lower energy potential would be very highly stressed (and short-lived), indeed.

Gale Banks has a very informative article on diesel turbocharging and he goes into some of this, here: http://www.bankspower.com/techarticles/show/27-why-diesels-make-so-much-torque

On edit: While we're in a practical vein, here's an article in HotRod about a comparison of using E85 vs 104 Octane racing fuel. Indeed, it does allow one to bump the ignition curve and increase compression/boost levels, but it does come at a cost of a 25% loss in fuel milage compared to gasoline. Some older cars will need attention to fuel system components to run E85. Flame travel is slower with E85 so there may be a problem with detonation, but that can be managed by shaping the combustion chamber and piston tops to reduce hot spots. Otherwise, this article says the 85/15 alky/gas mix works remarkably well for high performance engines. http://www.hotrod.com/techarticles/hrdp_0801_e85_ethanol_alternative_fuel/viewall.html

Hogwash. HooptieWagon Sep 2013 #1
The wording of the article is misleading, I agree. NYC_SKP Sep 2013 #4
they improved combustion of ethanol by increazing spark advance which higher octane ethanol or Bill USA Sep 2013 #7
The stoichiometric ratios for gas and alcohol are vastly different. HooptieWagon Sep 2013 #12
You are, sadly, misinformed. EPA uses the Heating Value of ethanol compared to gasoline's HV Bill USA Sep 2013 #14
I got over 40 years experience working on engines. HooptieWagon Sep 2013 #20
I never said one could optimize engines to runon ethanol & double th fuel efficiency of current FFVs Bill USA Sep 2013 #21
three MIT scientists designed a DI turbocharged engine with ethanol (DI) that gets 25-30% better mpg Bill USA Sep 2013 #22
CORRECTION: Ethanol's Fuel Efficiency (per EPA) is DOUBLED by the Ethanol DI turbocharged engine Bill USA Sep 2013 #24
Ethanol's portion of the increase in price of food 9.8% - 15.7%, Energy's portion: 35% - CBO Bill USA Sep 2013 #25
read the article. your comment doesn't apply towhat they did in their study. Bill USA Sep 2013 #5
Essentially, for your truck, you're correct. House of Roberts Sep 2013 #6
see comment 22 Bill USA Sep 2013 #23
More horsepower better mileage very cool. RGinNJ Sep 2013 #2
Be that as it may, Ethanol's Energy Content is 33 percent lower than Gasoline. NYC_SKP Sep 2013 #3
thats not the whole picture. octane rating is important cause you burning the fuel under compression Bill USA Sep 2013 #8
Yes. Neither is burned with 100% efficiency. Any improvement in either is great! NYC_SKP Sep 2013 #9
it's okay to be skeptical. Here is a link to a report on research by Michael Wang, U.S. Argonne Bill USA Sep 2013 #19
You can easily adjust spark advance, but not compression ratio. So, you won't get optimal results leveymg Sep 2013 #27
it's done by having computer control a turbo-charger. Fuel is monitored for alcohol content which Bill USA Sep 2013 #28
Of course, with the same variable boost you can achieve higher MPG running gasoline than alky leveymg Sep 2013 #30
a higher octane, higher latent heat fuel (ethanol, methanol) will always enable higher boosts than a Bill USA Sep 2013 #33
As a practical matter, gas engines rarely run more than 15 pounds boost (1.0 bar) on the street leveymg Sep 2013 #34
I object... PamW Sep 2013 #69
and I object to people misquoting or misrepresenting what i said. Bill USA Sep 2013 #70
What tune are you singing... PamW Sep 2013 #71
your personal attack on me does not make up for your lack of an argument. You are claiming that I Bill USA Sep 2013 #72
I have no problem with the paper PamW Sep 2013 #79
your personal brand of logic seems to allow you to assert "A" and "not A" simultaneously. Bill USA Sep 2013 #95
We have a 2014 ford focus madokie Sep 2013 #10
the article refers to a study (link provided) that involved altering the ignition timing of the cars Bill USA Sep 2013 #15
With E85 our miles per gallon went down madokie Sep 2013 #16
the study referred to in the article in OP points out that current FFVs CAN DO MUCH BETTER- IF THE Bill USA Sep 2013 #18
Correct me if I'm wrong but... wercal Sep 2013 #29
this won't happen but what should be done is add methanol to the ethanol for blending with gas. In Bill USA Sep 2013 #35
Why not skipnthe methanol wercal Sep 2013 #38
the cost of buiding the infrastructure to distribute it would be enormous. The cars are not cheap. Bill USA Sep 2013 #39
Natural Gas has been used in souther Europe for decades wercal Sep 2013 #40
how much pressure is the gas under in your brother's car? see link Bill USA Sep 2013 #43
cost of CNG fueling station $10,000 to $2 million. Which do you think is the commercial application? Bill USA Sep 2013 #45
I work in construction. 2 million doesn"t scare me at all. wercal Sep 2013 #46
I expect you'll be buying the NG Civic for an additional $10,000?? be my guest. Bill USA Sep 2013 #48
No but I'm in the market for.an aftermarket kit for alot less. wercal Sep 2013 #50
nothin to worry about there..... Bill USA Sep 2013 #61
You do understand that NG is considered wercal Sep 2013 #63
I am not questioning NG. I am commenting on using aftermarket add-on kits. Bill USA Sep 2013 #74
like $6,500 and if you want a compressor at home .. that will cost $3,500 Bill USA Sep 2013 #66
in Brazil 16 million. Bill USA Sep 2013 #51
Ethanol is heavily subsidized in Brazil. wercal Sep 2013 #52
documentation?? of course, you asked how many cars on ethanol, right? Bill USA Sep 2013 #54
http://scarcewhales.blogspot.com/2009/10/petropolis-and-brazilian-ethanol.html?m=1 wercal Sep 2013 #56
the Real cost of oil/gasoline: Over $5.28 a gallon National DEfense Council study Bill USA Sep 2013 #58
Consumer care about any of that is less than zero wercal Sep 2013 #62
almost all the of ethanol consumed @ a 10% blend used by all drivers in U.S. in 2012 13.2 billion Bill USA Sep 2013 #65
the reason we don't have more E85 pumps is that Oil industry has been fighting it like crazy Bill USA Sep 2013 #75
cost of Brazil's ethanol subsidy is TRIVIAL compared to STAGGERING costs of Global Warming Bill USA Sep 2013 #64
note I did NOT say NG was not viable. Just that converting it to methanol would be a better way to Bill USA Sep 2013 #73
Doesns't matter if it doesn't scare you. You have to have a credible business plan toconvince a bank Bill USA Sep 2013 #94
Gas(avg all grades): $3.63. Ethanol retail (avg): $2.95.. corn down 30% ovr 1 yr (see links) Bill USA Sep 2013 #47
Most consumers are smart enough to know that ethanol still costs more wercal Sep 2013 #49
Ethanol price 20% less than gasoline. E85 actually gets about 20% less mpg than gas powered car as Bill USA Sep 2013 #53
Consumer Reports found it to be a 29% deficit wercal Sep 2013 #57
even so (no links again) given the real price of gas is $4.60 - $5.60 ethanol is far cheaper. Bill USA Sep 2013 #59
Honda sells two FFVs in BRazil only, that achieve comparable power, torque and mpg as gasoline cars. Bill USA Sep 2013 #60
the 'joke' is it does not have to be this way. see OP Bill USA Sep 2013 #100
You are correct madokie Sep 2013 #67
Ethanol brings down the price of gas ~20% - Merrill Lynch - more than makes up for E85 price LOL Bill USA Sep 2013 #76
(Another) Economist (not ML) says RFS saves drivers up to $1.50 per gallon - Biofuels Digest Bill USA Sep 2013 #86
what do they pay for gas (unsubsidized) in Europe? Bill USA Sep 2013 #55
some more info on methanol which should be added to ethanol to be blended with gasoline. Bill USA Sep 2013 #36
This weekend I got 55mpg on our city blend postulater Sep 2013 #11
What blend of ethanol? E10? E15? E85? NickB79 Sep 2013 #13
I included a link (in OP) to report on the study. You have to look there 4 the details. E85 mostly Bill USA Sep 2013 #17
You have hit on one of the big drawbacks of ethanol wercal Sep 2013 #31
the reason there are so few stations with pumps for E85 is the Oil Industry has lobbied to keep Bill USA Sep 2013 #32
I'd like to see an example of the oil lobby wercal Sep 2013 #37
If you were working at EPA or Dept of Energy you would be falling over Oil industry lobbyists all Bill USA Sep 2013 #41
oil industry one of the biggest players in lobbying Government Bill USA Sep 2013 #42
So is the corn lobby wercal Sep 2013 #44
go to link to see very good articles in BusinessWeek, Consumer Federation of AMerica, & others that Bill USA Sep 2013 #77
Lets break down exactly what you are saying wercal Sep 2013 #80
obtuse arguments ignoring realities of starting a new product or integrated product delivery system Bill USA Sep 2013 #81
Microsoft doesm't own the computers wercal Sep 2013 #89
the operating system on all IBM PCs is written by Microsoft. Actually, Microsoft DOES OWN computers Bill USA Sep 2013 #90
You really have no idea do you? wercal Sep 2013 #91
pretending you can't read my comment (90) are you?? to quote myself: Bill USA Sep 2013 #92
don't wander off the point. in cmnt 81 I addressed your errors thus: Bill USA Sep 2013 #93
the question is not whether microsoft OWNs but did they write the operating systems use on IBM PCs Bill USA Sep 2013 #98
regarding muscling independent retailers to not make E85 available is restraint of trade violation Bill USA Sep 2013 #82
Independent fuel retailer attributes success to ethanol blends Bill USA Sep 2013 #83
Shocking - A 'good news ethanol story from Iowa wercal Sep 2013 #88
NG vehicles Methane Emissions raises their CO2e emissions to >2x diesels - PennState Bill USA Sep 2013 #99
I am merely repeating the reports published in Wall Street Journal, and by Bill USA Sep 2013 #84
Water used to make one gallon of Ethanol: 2.7 gal; to make a gallon of gasoline: 97 gallons Bill USA Sep 2013 #85
Its not a matter of how much water is used... wercal Sep 2013 #87
Note that I am advocating adding methanol to ethanol, precisely because we need more fuel Bill USA Sep 2013 #96
oil refineries in IOWA - and proposed Hyperion Tar Sands refinery Bill USA Sep 2013 #97
yeah, I just can't forget the secret Energy Task Force meetings CHeney had with all those...FARMERS! Bill USA Sep 2013 #78
Good news, but (maybe) automakers wont do it because of emission standards? DJ13 Sep 2013 #26
So what is the alternative to ethanol blended gasoline? 4dsc Sep 2013 #68
In the near term newblewtoo Sep 2013 #101
NG vehicles Methane Emissions raises their CO2e emissions to >2x diesels - PennState Bill USA Sep 2013 #102
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