'Curs to me a fast flame front can be corrected with ignition timing. Complete combustion could be a beautiful thing though! the fix is a slight delay in timing, move it forward.

It is pre-ignition due to heat and compression that could be problematical...

Dunno what the heat increase factor is in an 8 to 1, or 11 to 1 engine - but it can be modified.

Direct method is to lower the engine operating temp - BAD IDEA! The materials it's made of are engineered to wear best at a set (normal) temperature range. This is why tossing a thermostat away is a crummy fix for overheating at any time. Without a thermostat, the engine runs too cold, wears out faster, and sooner than you'd like you are DONE!

COLD AIR INTAKES reduce the intake air temp, and thus the air/fuel charge temp before compression. This is helpful because engine space air is heated by many things:

The radiator, the A/C condenser in front of it, the exhaust manifold(s), and the engine block and heads themselves. Heat also rises - so if your ducting leaks it sucks in very hot air! I've often wondered if insulating air intake ducting would be useful.... Heat can also transfer through the duct walls.

A turbo or super charger also compresses air ahead of the engine intake - this heats it, it then is compressed inside the cylinders which raises the heat level even further, and there you go... Multiplicative heat factors leading to Pre-Ignition/Detonation.

I can see a low flash-point causing early ignition due to temperature under compression, but I don't buy it necessarily as a leading cause for catastrophic failure or melted piston tops. Not unless a vehicle is completely abused and neglected. Something else must necessarily be going on.

Lower BTU's per unit volume, reduced production of gas expansion and therefore pressure to drive a piston down - yes, those I can see.

I feel that something is missing - and that also there is some confusion of issues. Timing for example is one thing, precombustion is a seperate issue. Precombustion (firing before an ignition impulse is delivered by the ignition circuit) is an indication of either VERY LOW OCTANE (ability to resist combustion under heat and pressure) or something badly mechanically wrong!

Since methanol and ethanol BOTH increase octane and also have lower combustion temperatures- it just does not figure.

Still studying this. Sell me it - but be ready when you realise I'm not just some dope off the street...
My Poppa was an Engineer, and I'm a TECH.
~STRICTLY SPEAKING~

~Wolfie

 

The above paragraph shows that you simply don't know some basic concepts (physics) behind internal combustion engines. So here are some reading for you: Thermal efficiency - Wikipedia, the free encyclopedia
Gas laws - Wikipedia, the free encyclopedia
Furthermore, I'm almost certain that the larger volume of gas from ethanol is BS, but I'm not going to verify that right now. And BTW, the volume of the gas is dependent on the temperature!! (gas laws)

 

thosfsull:
I realize you are paraphrasing that from a book, but in the first paragraph, the difference in combustion temperatures is intriguing. In my experience, exhaust gas temperatures (good indicator of combustion temperatures) were very similar between gasoline and E85. I wonder how much differently straight ethanol behaves than the 85% mixture.

Greywolf:
Higher octane gasoline has a higher flame speed than lower octanes. The difference is in the autoignition temperature. With ethanol, the spark advance is usually increased farther before TDC. Combustion propagates from the spark plug outward along what's called the flame front. This also creates a pressure wave traveling outward from the source of ignition. Pre-ignition or spark knock occurs when this pressure wave outruns the flame front and the combination of pressure and temperature cause ignition in the end gas region (farthest from spark plug) which creates a flame front and pressure wave in the opposite direction. Where those two pressure waves meet in the middle is where the piston damage occurs and is what causes the pinging sound that is heard (imagine striking the top of the piston with a ballpeen hammer). The faster flame speeds ensure that the flame front and pressure wave both reach the end gas region closer to the same time so that the end gases are ignited by the flame front as opposed to the pressure and heat.

Aurgathor:
I already said what he said and you didn't have a problem with it then. Due to the different air/fuel ratio required for stoichiometric ratio of ethanol, there is more fuel per unit of air. More moles of reactants equals more moles of products in the chemical reaction, equaling more pressure in the combustion chamber which generates more mechanical work. It's not b.s., and BTW, the volume of the gas in the combustion chamber is only dependent on the geometry of the engine. If you can fit more mass into the same volume, you will generate more pressure.

 

If you want a direct comparison here it is...

using my 2000 Ranger as a test bed, I used E85 for a tank (yes there will be a little contamination from the left over regular that was in there) and did my normal daily driving with it. Over the course of that tank I got roughly 17 mpg. The next tank I filled with regular 87 octane and did roughly the same daily driving and averaged 19.2 mpg.

Given the inaccuracies in my "non-scientific" methods that's pretty close to the same for me. And if you factor in the fact that E85 is about 20 cents a gallon cheaper, it's just about a wash in the pocket book.

Now, that said, it does seem that my truck runs better on E85 than 87 regular. With the regular is has a very rough idle and has a tendency to ping, especially when the weather is warm. With the E85, both of those are gone and it feels like it has a little more "pep" on the top end.

Anyway, just my observations from running a couple tanks.

Edit: just have to add that our "87 regular" is now mandated as E10, so I guess it's not a good comparison against true E0 regular.

 

Can you take my Physics and other hard sciences CLEPS for me?

About the College Level Examination Program (CLEP)

 

I don't have the hard science knowledge or mechanical ability that the majority of the guys here have. I am just attempting to add to the conversation as best that I can. Most of my points will be coming from a straight ethanol perspective and when I can I will find some e85 claims by that author I referenced. Assume everything to be very pure ethanol with nothing extra, unless noted from when I reference.

Interesting enough, I read a section last night on people using e85 in regular cars that weren't flex fueled. Little to no problemo for them too.

My goal this summer is to make a still and brew my own fuel or at least try to do so. I don't have e85 anywhere near me in South West Jersey (across from Philly). So anyway I can keep my father's and my gasoline powered trucks moving on the cheap I will at least make a respectable attempt.

 

What gas law(s)? There are at least 23 of them.

Boyles Law for example, is used extensively in turbine engine design.

 

I may have missed it, not read it all, or whatever. It doesn't mean much.

Awright, so lets do some math:
ethanol is C2H5OH and its molecular weight is: (2 * 12) + (6*1) + 16 = 46
gasoline can be *approximated* as C8H14, and the molecular weight is: (8 * 12) + (14 * 1) = 110.
(note for the nitpicky: I used round numbers to simplify the computation)

So, 55 mole of C2H5OH will weigh as much as 23 mole of C8H14 (55 * 46) = (23 * 110) = 2530

So let's burn an equal weight of both. (55 and 23 units)
From ethanol, we get (2 * 55) = 110 CO2 and ((6 * 55) / 2) = 165 H20
from gasoline, we get (8 * 23) = 184 CO2 and ((14 * 23)/2) = 161 H2O

So around 67% more CO2, and about 2.5% less H2O!

Because of different stoichiometric ratios, the actual difference won't be as big (will compute that tomorrow) but the claim that "alcohol generates a larger volume of combustion gases than gasoline" is most certainly BS.

Yes, that is undeniably correct.
However, when doing comparisons, the usual procedure is to do the measurements at the same pressure and temperature.

yes, and that's where the gas laws come in.

 

The link I provided only has a handful of them. Use the combined law.

 

Making fuel grade ethanol in some ways is harder than making ethanol for drinking. For one, you can only get to around 96%. And you'll most likely use up more fuel than what you get back.

 

So for the same mass of fuel, there are more moles of ethanol than gasoline. Exactly what was said earlier. Plus when you take into account that the stoichiometric ratio of ethanol is nearly 9:1 and gasoline is approximately 15:1 (mass ratios), ethanol at stoichiometric ratio will have more moles of exhaust than gasoline at stoichiometric ratio. I think you proved my point. Also when doing the calculations, not necessarily should they be performed at the same temperature and pressure if that does not accurately represent the dynamic combustion chamber. Also, fuel grade ethanol can be made at 100%, but it is denatured with gasoline to keep people from drinking it. The E100 that the Indycar series is running isn't exactly E100, but the difference is not made up in water.

Ethanol from corn does not break even in terms of the energy out vs. the energy to make it. Ethanol from sugarcane in Brazil does, though. I also read last night that biodiesel derived from algae gets 3.2 units of energy out of the fuel for every 1 unit of energy derived from petrol used to make that biodiesel.

 

Hi- Quickly read some of recent posts here and want to suggest you discuss gasoline composition, instead of science of octane and FV (fuel efficiency).
It's the sum of the gasoline ingredients that determines octane measurement/rating and ignition and burning rate in conjunction with the type of engine (fuel system) gasoline is running in.

All the scientific calculations may be interesting to some -but does not help most to understand if ethanol blends of fuel are appropriate for their type of engine and whether or not they will experience a significant drop in mileage/efficiency, or engine damage.

ASTM standards may help you better understanf gasoline composition.
(Most types of gas contain hundreds of separate ingredients/chemical/compounds- ethanol is just one of many that effects octane, etc.)

As for the multiple laws that lead up to switchover to E10, there's not a single "federal" law that mandates E10.

Recent (past 10 years) Federal laws have required an increase in "renewable" fuels.
"Alternative" fuels (by definition) is not the same as "renewable" fuels.

I can't decide which laws would be most useful to you (Depends on if discussion is on E10, E85 or ALL renewable and alternative fuels- But, I'll post a few links to send you in right direction.

Important:
How each state chooses to meet their "quota" for renewable fuels, is up to individual state laws. (Check your state's government website, usually found under State Dept. of Energy or Agriculture).

Below links do not direct you to actual original laws, but rather to current useful information:
EPA - Renewable Fuel Standard (RFS) Program:
Standard Program | Renewable Fuels | US EPA

U.S. Dept. of Energy Efficiency and Renewable Energy (EERE):
Alternative Fuels and Advanced Vehicles Data Center: State and Federal Incentives and Laws

American Coalition for Ethanol (ACE) State-by-State Handbook 2007:
http://www.ethanol.org/pdf/contentmg...s_07_web-1.pdf
(Includes renewable fuel use, requirements, labeling laws for each state).

Note: Many states have passed laws in 2008 which dramatically changed/effect info contained in 2007 ACE handbook, prepared by ethanol.org).

Also keep in mind, who ACE is:
Quote from their website: "about ACE
The American Coalition for Ethanol (ACE) is the grassroots voice of the U.S. ethanol industry, the nation's largest association dedicated to the production and use of ethanol".

---------------
My opinion: Using E10 to meet "renewable" fuel requirements makes absolutely no sense. U.S. has failed in promotion/supply of E85 and E100 gasolines and vehicles -
One of many reasons for unfortunate rapid increase in E10 everywhere. (E10 is a very non-efficient, inconvenient and costly way to meet quote/mandate for renewable fuel).

E10 also sometimes refers to gas with ethanol added for oxygenation (since MTBE was banned).

E10 (10% ethanol) was never intended to be classified as a "renewable fuel", nor to be our primary source for renewable fuel.

But without supply and acceptance of appropriate types of "renewable" fuels here in U.S.
most states believe they have no other choice now, than to add 10% ethanol to gasoline sold at most public gas pumps -to meet their renewable fuel quotas...

This has caused confusion, unnecessary expense and engine problems for typical consumer.

By law, only 10% ethanol can be added to conventional fuel.
Auto and marine manufacturers only permit 10% or less (due to the know engine damage alcohol fuels over 10% will cause).

E85 would have been a better method to meet renewable fuel standards - U.S. failed for various reasons in promoting E85... Reasons include lack of availability of E85 pumps everywhere, (despite huge government tax credits/subsidies), leaking (and UL issues) from E85 pumps installed, cost to produce E85 too high to encourage public to purchase E85 cars/trucks - -(E85 energy value is about 40% lower).

BTW, problem with fiberglass tanks was only limited to one marine brand, made in 1960's -70's, which used polyester resins - ALL other fiberglass tanks made are resistant to ethanol.
See RFA Important News for Boaters (I think it was published around 1995):
http://www.ethanolrfa.org/objects/do...oat_owners.pdf
While I feel bad for those whose engines were destroyed from ethanol fiberglass melting - this topic is very old and not relevant to current E10 use.

For those of you still interested in comparing the octane, burning rate, latent heat of vaporization and energy efficiency of ALL various types of gasoline,
drivingethanol.org site has a useful chart with reliable values:
Racing Fuel Characteristics
(Chart includes all gasolines not just racing fuel).

All info/links listed above are summarized in my website...In the future can I post links to my site pages instead,
to save time in supplying you ethanol info?

 

Greywolf,
How do I send you a private message?
If not possible here, please email me at fuel.testers@yahoo.com

I'm committed to providing public (including Ford engine owners) PRACTICAL info on ethanol fuels/laws, but this thread seems to be focused on SCIENCE of ethanol, which unfortunately I don't have time to participate in right now.

It's the precautions, dangers etc. of E10 that public is currently most confused about.
Examples:
- Many engine parts (especially older engines) may not not designed to resist alcohol gasoline -
- Many states do not label pump E10, so consumers still may not realize they're filling up with an alcohol blend of gas...
- Since ethanol (oxygen rich) changes ignition and burning rate of fuel, there's important facts all engine owners need to be aware of to properly manage fuel (eg. oxygen sensors, piston damage, etc...
- Ethanol alcohol is an excellent solvent, degreaser etc.
(reason you find it in so many fuel system cleaning products) - -
But it's the solvent capabilities of alcohol that's causing the most problems when people switch to E10 (E.G. clogged fuel filters, gas contaminated with dirt, rust, - drying out and cracking of parts, etc.

I would like to get practical info on this board -
Should I start a new thread titled - E10 PRECAUTIONS?

For those here just beginning to understand how E10 has changed all fuel system management rules,
Check gasoline for alcohol yourself, and avoid ethanol-blends of gasoline, until you know how to properly manage it.

E10 is safe for most newer auto engines in excellent condition, and should only decrease mpg 3% or less.

E10 will keep a clean fuel system clean (without need for external products).
Ethanol also adds benefit as a gas antifreeze (ask anyone in Alaska, they've been adding ethanol to tank for this positive effect).

But the negative side-effects of E10 outweigh the positives for the majority.

The amazing water-absorbing abilities of ethanol, make it not suitable for marine engines.
The high oxygen content makes it unsuitable for older engines without oxygens sensors and modern emissions fuel systems...

I've had many discussions with motorcycle owners/companies recently, who also believe E10 is not suitable for motorcycles. (mainly due to driveability, acceleration and performance issues).

Most high performance engines need to be specifically adapted to run properly on E10 and other percents of alcohol fuels.

Alcohol fuels can increase speed and acceleration when engine properly designed to run on alcohol fuel, reason used for racing.

But again, it's the typical conventional auto or truck owner, that needs to understand E10 better, to manage it without any negative effects.

Most engines on the road can use E10, but the degree of precautions vary considerably.

I believe marine engines should always avoid E10 - Oil and water don't mix, ethanol attracts and absorbs water - There is not a single type of water-separating filter, including 10 micron, that can prevent removal of all water marine engines are exposed to.

Less common in 2008, but few years back (2004-2005) when E10 first was required in high ozone states, many pumps had improper mixtures of E10.
Gas contained 20, 30 and 40% ethanol at times!
Testing by consumers reveals above legal limit of ethanol still occurs- most common when individual fuel distributors first start ethanol blending.

Many believe it's intentional (adding extra ethanol, since it's cheaper than petroleum), but I don't. I speak with distributors all the time.

It's taken too long for consumers to pay attention and speak out about ethanol (E10).

Fuel (petroleum) has far greater ramifications than E10 engine precautions -
(Petroleum is 8% of U.S. GNP, determines our relationships with foreign countries, environment/pollutions, etc.).

I've had the opportunity to make others more knowledgeable on these important topics, probably because of a simple and inexpensive ethanol fuel test kit I supply. Kind of ironic, and funny, that something so simple would lead people to better understand the most important issues in the U.S. today.

AFTK's (Portable Alcohol Fuel Test Kits) and comapany name Fuel-Testers is not my primary business - By now, I thought this product would no longer be necessary. (Gas station owners SHOULD be testing alcohol content of fuel, not consumers).
But in the meantime, if testing by consumers will help change laws dictating the future of U.S. I think supplying alcohol testers was one of the best decisions I've ever made to have a positive impact on others.

If nothing else, I hope those reading my posts are encouraged to contact their local state representatives to improve consumer protection laws with e10 - Contact federal governemnt representatives, including President Bush and EPA too-
Interesting CNN article titled: Bush Administration offers new fuel economy rules:
Bush administration offers new fuel economy rules - CNN.com


Also hope it will encourage many to switch to renewable (non-petroleum) fuel vehicles.
Whether it's hybrid, solar-powered, electric or any other type of alternative or renewable fuel vehicle - if each of us decrease our petroleum use it will have a very positive impact on the future of the U.S.

If you're not ready for an advanced alternative vehicle, at least consider purchasing a Flex Fuel Vehicle when E85 pumps are available in your area.
I don't see E85 vehicles as a long-term solution.

E85 gas usually costs more, and may actually increase pollution from ethanol producing plants, but decreased petroleum use will at least place the U.S. in the right direction.
Also See more E85 pump issues: http://www.eere.energy.gov/afdc/pdfs/statesummary.pdf

Must mention anyone heavily invested in petroleum stocks and mutual funds will not agree with me that decreasing petroleum is positive - but for the long term, the U.S. MUST support non-petroleum sources of energy.

Currently, more than half of petroleum the U.S. uses/requires is imported from foreign countries -
In 2006, U.S. supply 10%, U.S. use 24%.
View statistics:
EIA - Petroleum Data, Reports, Analysis, Surveys
Energy Information Administration - International Petroleum (Oil) Imports and Exports Data

Due to company and residence relocation this month, I may not get back to thread soon - but encourage you to continue discussing these issues (whether you agree with me or not) and feel free to email or call me with any urgent questions.

Good Luck -

 

You need to make 25 posts on this forum before you can use the PM function.
to use, just click on the username and select that option, it's all in the FAQ's

 

[quote=fueltesters;6223948]

You'll notice most models of FFV's (E85) in U.S. are pick-up trucks and cars designed/styled for government use -(due to forced requirements for current gov't vehicles purchased).


Does a 2000 Ranger fall into that category? It is black..... Ext..flareside...loaded.....maybe to fit in with those black helicopters??? I am 2nd owner,don't think it was government owned. Dealer said some lady owned it.