E85monster: Conversion for E85
Thread Starter
Tech Contributor
Joined: Mar 2003
Posts: 12,092
Likes: 197
From: Colorado Springs, CO
St. Jude Donor '08-'09-'10-'11
E85monster: Conversion for E85
Before getting into this write-up, I would like to ask each person reading to know a big part of my motivation is the St. Judes fundraising effort on this board. I dont think its much of a reach to understand why this cause is so important but unless you suffer such a painful loss as a result of a childnood destroyed by various illnesses I dont think you could see it from the point of view of it happening to your world. The death of a child in your life changes you forever and I will never be able to relay the pain associated with it. Take a moment and send 25 bucks to this charity. You wont even have to do anything more than you do in posting on your computer on this forum. Its the best thing you can do to help this world and make my efforts here more worthwhile. We have the means to send robots to mars so I believe we can beat cancer, sudden infant death, and form new medications.
---------------Make a difference TODAY------------------
This year you can donate in 3 ways:
1) Personal checks, cashier checks, or money orders, made out to: St. Jude Children's Hospital and mailed to "pewter99,":
Robert Briggs
P.O. Box 17083
Clearwater Fl 33762
Please put your forum name on the memo line of the check
2) paypal: corvettes4stjude@aol.com
#3 New donation option
3) St. Jude Donation page - we get credit for this:
https://waystohelp.stjude.org/sjVPor...1&programId=51
I WANT TO SEE ST.JUDES DONOR 09 UNDER EVERYONES NAME THIS YEAR!!!
Since these threads are stickies, I'm getting lots of PMs to argue things. This one is high up on the list so let me add this EDIT: E85 is race gas and sould be compared to the cost of race gas, not 87 or 93 octane pump gas. If it bothers you that this 105 octane is more cost to run on a comuter car daily, get meth injection. E85 burns at a faster rate and will reduce your cars range on a tank of fuel. For those sitting there calculating the cost per mile to use it, dont waste your time reading this. For the guy who wants 12-20+ rwhp for a tuning change to use this while having 105 octane race gas for a small additional fuel cost, you do get the point.
Myths and Urban legends:
Before getting into a discussion I want to get rid of some of the myths about E85. E85 is ethanol (not methanol) and is not corosive to our fuel lines, rubber o-rings, ect. There have been a number of conversions done to corvettes and other LS based engines and here are some FACTS about the use of E85.
1- It burns cleaner than gas.
2- It has an octane rating of 105-106.
3- It burns at a lower Stoic of 9.765
4- It burn temps
5- When tuned for its use it produces more HP in the same engine
6- It requires more injector for the same HP level (by about 1.47x)
7- It requires more fuel pump volume capability for modded cars.
8- The engines using it once torn down are cleaner. If you look on the links below you will see actual instances of cars attaining better economy and power and upon tear down (after 110k miles in one instance) the engine was super clean and had no failures in normal GM parts for gas engines.
Jay Leno's E85 stroker vette 600HP:
The Katech built E85 440:
Now in most cases where a corvette owner wants to use E85, just an injector swap so you dont max out injector flow and a tune is needed. Lets repeat that a different way....if you dont tune for the new timing curve and lean it out, you will not make more power and your economy will be worse.
Tuning constraints: Stoic gets changed to 9.765:1. Our cars use a table for stoic that also adjusts for ethanol content. Most fuels have 10% ethanol in them. In this HPtuners screen shot, you can see that by varying the stoic amount from the 10% end at 14.69 to the 87% cell which you would use 9.765, you would be able to use any available fuel and the car would adjust the tune automatically by composition just as flex fuel vehicles now do. If you have 1/2 a tank of E85 and cant find a E85 station, just use regular gas and the car would self adjust. Is this composition sensor already in our corvettes? If not these cells all get the same 9.765 to run E85. If the composition sensor is in fact in there use the fuel thats available and the PCM self adjusts as you scale these cells from 14.4 for 10% down as ethanol content rises. Keep in mind that compression if altered for E85 use isnt adjustable but there are table for PE spark advance that is for alcohol use. I will check for a flex fuel tune in the HPtuners repository to see how GM adjusts these tables for use of currently available flex fuel vehicles that can readily switch back and forth between these fuels.
In the corvette project seen here they gained about 30hp and 15tq at the wheels by being able to increase timing and lean out the car.
Here is a corvette conversion article (please read it before posting false info that is already discussed in it) :
http://www.vetteweb.com/tech/vemp_08...ion/index.html
Another article on a conversion in a ford truck:
http://e85vehicles.com/converting-e85.htm
A picture is worth a 1000 words:
Here are some vehicles running E85 and kits available for tuning them. Keep in mind that a HPtuners owner needs nothing from these kits except bigger injectors.
http://www.rune85.com/
Lastly, a car running E85 can run up to 13:1 compression and take advantage of the power and economy asscoiated with it. If you dont change these things, economy suffers but if thats more important than the need for 105 octane, you dont get the point.
Questions, comments, opinions??
BUT where can I get E85....check your area with this map service:
You simply take the corn and squeeze it hard against the gas tank port like this:
Just kidding....go here to find the station near you selling it.
http://www.e85refueling.com/
---------------Make a difference TODAY------------------
This year you can donate in 3 ways:
1) Personal checks, cashier checks, or money orders, made out to: St. Jude Children's Hospital and mailed to "pewter99,":
Robert Briggs
P.O. Box 17083
Clearwater Fl 33762
Please put your forum name on the memo line of the check
2) paypal: corvettes4stjude@aol.com
#3 New donation option
3) St. Jude Donation page - we get credit for this:
https://waystohelp.stjude.org/sjVPor...1&programId=51
I WANT TO SEE ST.JUDES DONOR 09 UNDER EVERYONES NAME THIS YEAR!!!
Since these threads are stickies, I'm getting lots of PMs to argue things. This one is high up on the list so let me add this EDIT: E85 is race gas and sould be compared to the cost of race gas, not 87 or 93 octane pump gas. If it bothers you that this 105 octane is more cost to run on a comuter car daily, get meth injection. E85 burns at a faster rate and will reduce your cars range on a tank of fuel. For those sitting there calculating the cost per mile to use it, dont waste your time reading this. For the guy who wants 12-20+ rwhp for a tuning change to use this while having 105 octane race gas for a small additional fuel cost, you do get the point.
Myths and Urban legends:
Before getting into a discussion I want to get rid of some of the myths about E85. E85 is ethanol (not methanol) and is not corosive to our fuel lines, rubber o-rings, ect. There have been a number of conversions done to corvettes and other LS based engines and here are some FACTS about the use of E85.
1- It burns cleaner than gas.
2- It has an octane rating of 105-106.
3- It burns at a lower Stoic of 9.765
4- It burn temps
5- When tuned for its use it produces more HP in the same engine
6- It requires more injector for the same HP level (by about 1.47x)
7- It requires more fuel pump volume capability for modded cars.
8- The engines using it once torn down are cleaner. If you look on the links below you will see actual instances of cars attaining better economy and power and upon tear down (after 110k miles in one instance) the engine was super clean and had no failures in normal GM parts for gas engines.
Jay Leno's E85 stroker vette 600HP:
The Katech built E85 440:
Now in most cases where a corvette owner wants to use E85, just an injector swap so you dont max out injector flow and a tune is needed. Lets repeat that a different way....if you dont tune for the new timing curve and lean it out, you will not make more power and your economy will be worse.
Tuning constraints: Stoic gets changed to 9.765:1. Our cars use a table for stoic that also adjusts for ethanol content. Most fuels have 10% ethanol in them. In this HPtuners screen shot, you can see that by varying the stoic amount from the 10% end at 14.69 to the 87% cell which you would use 9.765, you would be able to use any available fuel and the car would adjust the tune automatically by composition just as flex fuel vehicles now do. If you have 1/2 a tank of E85 and cant find a E85 station, just use regular gas and the car would self adjust. Is this composition sensor already in our corvettes? If not these cells all get the same 9.765 to run E85. If the composition sensor is in fact in there use the fuel thats available and the PCM self adjusts as you scale these cells from 14.4 for 10% down as ethanol content rises. Keep in mind that compression if altered for E85 use isnt adjustable but there are table for PE spark advance that is for alcohol use. I will check for a flex fuel tune in the HPtuners repository to see how GM adjusts these tables for use of currently available flex fuel vehicles that can readily switch back and forth between these fuels.
In the corvette project seen here they gained about 30hp and 15tq at the wheels by being able to increase timing and lean out the car.
Here is a corvette conversion article (please read it before posting false info that is already discussed in it) :
http://www.vetteweb.com/tech/vemp_08...ion/index.html
Another article on a conversion in a ford truck:
http://e85vehicles.com/converting-e85.htm
A picture is worth a 1000 words:
Here are some vehicles running E85 and kits available for tuning them. Keep in mind that a HPtuners owner needs nothing from these kits except bigger injectors.
http://www.rune85.com/
Lastly, a car running E85 can run up to 13:1 compression and take advantage of the power and economy asscoiated with it. If you dont change these things, economy suffers but if thats more important than the need for 105 octane, you dont get the point.
Questions, comments, opinions??
BUT where can I get E85....check your area with this map service:
You simply take the corn and squeeze it hard against the gas tank port like this:
Just kidding....go here to find the station near you selling it.
http://www.e85refueling.com/
Last edited by SpinMonster; Aug 5, 2012 at 07:18 PM.
Burning Brakes
Joined: Mar 2006
Posts: 790
Likes: 63
From: Ft Worth TX
I'll be watching this one
They started selling E85 at a Kroger near the house last year. I've been thinking about converting my 66 Chev Big Block pickup, but it would be a lot easier and cheaper to do one of my newer cars.
Can't wait to see what you do with the truck and the Vette!
Can't wait to see what you do with the truck and the Vette!
Melting Slicks
Joined: Oct 2000
Posts: 2,235
Likes: 65
From: Herndon VA
I've done a lot of E85 tunes and was one of the first to do it in a High HP FI application and actually document it. I thought I'd chime in with what I think and what I've experienced.
Overall, E85 is great stuff for a lot of reasons. I wish it was more available out here now since we just recently moved to the Boston area. I'm sure you'll be very happy with your conversion.
Plus it smells better than gas
1- It burns cleaner than gas.
True
2- It has an octane rating of 105-106.
True - although you have to be careful on consistent mixtures. I've seen everything from E50-E85 come out of an "E85" pump. The lowest it's supposed to go is E70 in most areas.
3- It burns at a lower Stoic of 9.765
True
4- It lowers IAT temps
True - but only at the valve. You don't get quite the improvement as you do injecting before the IM and you won't see the difference if you are scanning the IAT sensor obviously.
5- When tuned for its use it produces more power in the same engine and produces as good or better fuel economy. This is due to allowing you to run both leaner and with more timing. Cars that dont tune for the timing and a/f ratio and simply run the bigger injectors are the cars repsonsible for the bad fuel economy reports. Lets keep in mind that its not all about us in saving the marble. Running a cleaner fuel even if its a dead even wash for the cost is still with merit.
This is not true. It is true it will produce more power. It's also trickier for the average tuner without a dyno to get spark correct. I have spent countless hours on a dyno optimizing A/F and spark for E85. A lot really depends on the DCR of the motor.
What is not true is the same or better fuel economy. E85, by definition, has less energy per volume, thus the lower stoich ratio. You have to put in more E85 than gas. Again, I have done this in real life and NO car has done the same or better in fuel mileage. The people I see claiming this are the ones that change out injectors, don't change the tune, and read their mpg off their mpg DIC. It's not accurate if you don't change the computer to tell it you put in larger injectors...
I will say you can minimize the mpg loss through proper engine setup and tuning, however you will not make up all of the 29% loss in energy per volume. Maybe with direct injection, but not on any current LSx.
6- It requires more injector for the same HP level (by about 1.47x)
true
7- It requires more fuel pump volume capability for modded cars.
true
8- The engines using it once torn down are cleaner. If you look on the links below you will see actual instances of cars attaining better economy and power and upon tear down (after 110k miles in one instance) the engine was super clean and had no failures in normal GM parts for gas engines.
Very true. I've run E85 in my C6 since I've had it, but it only has CAI. I'm out of injector. I also ran it in an LS1 for several thousand miles making 650rwhp before a valvespring let go (918 madness) and when we tore it down, it was very clean.
True
2- It has an octane rating of 105-106.
True - although you have to be careful on consistent mixtures. I've seen everything from E50-E85 come out of an "E85" pump. The lowest it's supposed to go is E70 in most areas.
3- It burns at a lower Stoic of 9.765
True
4- It lowers IAT temps
True - but only at the valve. You don't get quite the improvement as you do injecting before the IM and you won't see the difference if you are scanning the IAT sensor obviously.
5- When tuned for its use it produces more power in the same engine and produces as good or better fuel economy. This is due to allowing you to run both leaner and with more timing. Cars that dont tune for the timing and a/f ratio and simply run the bigger injectors are the cars repsonsible for the bad fuel economy reports. Lets keep in mind that its not all about us in saving the marble. Running a cleaner fuel even if its a dead even wash for the cost is still with merit.
This is not true. It is true it will produce more power. It's also trickier for the average tuner without a dyno to get spark correct. I have spent countless hours on a dyno optimizing A/F and spark for E85. A lot really depends on the DCR of the motor.
What is not true is the same or better fuel economy. E85, by definition, has less energy per volume, thus the lower stoich ratio. You have to put in more E85 than gas. Again, I have done this in real life and NO car has done the same or better in fuel mileage. The people I see claiming this are the ones that change out injectors, don't change the tune, and read their mpg off their mpg DIC. It's not accurate if you don't change the computer to tell it you put in larger injectors...
I will say you can minimize the mpg loss through proper engine setup and tuning, however you will not make up all of the 29% loss in energy per volume. Maybe with direct injection, but not on any current LSx.
6- It requires more injector for the same HP level (by about 1.47x)
true
7- It requires more fuel pump volume capability for modded cars.
true
8- The engines using it once torn down are cleaner. If you look on the links below you will see actual instances of cars attaining better economy and power and upon tear down (after 110k miles in one instance) the engine was super clean and had no failures in normal GM parts for gas engines.
Very true. I've run E85 in my C6 since I've had it, but it only has CAI. I'm out of injector. I also ran it in an LS1 for several thousand miles making 650rwhp before a valvespring let go (918 madness) and when we tore it down, it was very clean.
Plus it smells better than gas
Thread Starter
Tech Contributor
Joined: Mar 2003
Posts: 12,092
Likes: 197
From: Colorado Springs, CO
St. Jude Donor '08-'09-'10-'11
Thank you for sharing real life experience.
All of the test cars produced more HP by virtue of the cooling effect of the IAT's and reduced detonation with its higher octane. Any and all Properly tuned vehicles will produce more power. You are correct that the fuel itself doesnt produce more power by volume burned.
I was very clear in stating that it must be "tuned for its use" and that includes spark optimization and leaning out the vehicle where it gains its economy by its lean PE fueling. A purpose built motor using E85 can be as efficient or more so if the fuel's qualities are all expolited. Compression is a major fuel economy component that isnt used in a retune like this.
For arguments sake I will say it equals the economy of gas only if taking into account the drop in cost associated with its use but the reality is that although the MPG is lower by 10-15% the fuel costs 20+% less and thus is better economy by dollar cost vs miles driven.
I would very much like to see a sharing of the actual tuning if you feel so inclined. I'm sure I can piece it together with no help but its nice to see a colaboration. If not, I understand trade secrets if its an income for you.
All of the test cars produced more HP by virtue of the cooling effect of the IAT's and reduced detonation with its higher octane. Any and all Properly tuned vehicles will produce more power. You are correct that the fuel itself doesnt produce more power by volume burned.
I was very clear in stating that it must be "tuned for its use" and that includes spark optimization and leaning out the vehicle where it gains its economy by its lean PE fueling. A purpose built motor using E85 can be as efficient or more so if the fuel's qualities are all expolited. Compression is a major fuel economy component that isnt used in a retune like this.
For arguments sake I will say it equals the economy of gas only if taking into account the drop in cost associated with its use but the reality is that although the MPG is lower by 10-15% the fuel costs 20+% less and thus is better economy by dollar cost vs miles driven.
I would very much like to see a sharing of the actual tuning if you feel so inclined. I'm sure I can piece it together with no help but its nice to see a colaboration. If not, I understand trade secrets if its an income for you.
Last edited by SpinMonster; Nov 25, 2011 at 01:33 AM.
Thread Starter
Tech Contributor
Joined: Mar 2003
Posts: 12,092
Likes: 197
From: Colorado Springs, CO
St. Jude Donor '08-'09-'10-'11
Does anyone know if E85 varies with cost in proportion to what gas costs? In other words when gas was 4 bucks a gallon, how much was E85?
Thread Starter
Tech Contributor
Joined: Mar 2003
Posts: 12,092
Likes: 197
From: Colorado Springs, CO
St. Jude Donor '08-'09-'10-'11
Here is the link from above:
http://www.e85refueling.com/
Le Mans Master
Joined: Oct 2007
Posts: 6,149
Likes: 11
From: Greater Detroit Metro MI, when I'm not travelling.
Hi Spin,
Great idea! Just a few pointers to make it not just work, but also last and be reliable for a long time:
- A lot of rubber compounds (hoses, O-rings, etc) are rated for usage with 10% Ethanol but will gradually deteriorate when exposed to 85%. If I did this conversion on my car I would try to double check that any lines or O-Rings in contact with the fuel are actually rated for it. It is never an issue right away, which is why there are conversions running around with zero modifications, but if the rubber is not meant for Ethanol usage it will crack sooner or later.
- Ethanol is a very good solvent. If there is any crap in your fuel tank, lines or filter, it will dissolve and move on to clog the filter or injectors. In an older car it is recommended to do a full system flush before you hook the end of the line up to the fuel rails. Probably not an issue with your vehicles though as they are both pretty new.
- Ethanol is very hygroscopic; make sure anything in contact with the fuel is stainless (I think it is).
- Cold starts with ethanol are a real problem because of the fuel's low volatility. As you probably know, more than 50% of the cars in Brazil run on straight alcohol. They used to completely refuse to start when it was below 50F or so, which contributed to the loss of popularity of Ethanol in the past. The new generation of Ethanol vehicles is a lot better in that aspect, but they almost always have a second tank holding Gasoline which is used for cold starts. Something to keep in mind.
- Fuel economy is always lower. I'm not talking about hacked together conversions here: The same car you can buy in South America with the exact same engine will make slightly more power and get slightly less fuel economy with Ethanol... Alcohol has a lower energy density, so you have to burn more of it to go the same distance... For example:
Uno Mille 14,3 km/l Gasoline, 10,1 km/l Ethanol
VW Golf 1.6 (13,6 km/l Gasoline, 9,3 km/l Ethanol
These aren't poor tunes or flex fuel vehicles: These are factory vehicles developed and optimized for either fuel, specifically.
Etc...
I don't have a lot of experience with conversions but a lot of the Alternative Fuels research I am currently doing for my employer is centered around more efficient Ethanol combustion, so this is a topic I'm very interested in. I've got a good sized library of books on the subject (that I need to get around to reading more of one of these days
)
Great idea! Just a few pointers to make it not just work, but also last and be reliable for a long time:
- A lot of rubber compounds (hoses, O-rings, etc) are rated for usage with 10% Ethanol but will gradually deteriorate when exposed to 85%. If I did this conversion on my car I would try to double check that any lines or O-Rings in contact with the fuel are actually rated for it. It is never an issue right away, which is why there are conversions running around with zero modifications, but if the rubber is not meant for Ethanol usage it will crack sooner or later.
- Ethanol is a very good solvent. If there is any crap in your fuel tank, lines or filter, it will dissolve and move on to clog the filter or injectors. In an older car it is recommended to do a full system flush before you hook the end of the line up to the fuel rails. Probably not an issue with your vehicles though as they are both pretty new.
- Ethanol is very hygroscopic; make sure anything in contact with the fuel is stainless (I think it is).
- Cold starts with ethanol are a real problem because of the fuel's low volatility. As you probably know, more than 50% of the cars in Brazil run on straight alcohol. They used to completely refuse to start when it was below 50F or so, which contributed to the loss of popularity of Ethanol in the past. The new generation of Ethanol vehicles is a lot better in that aspect, but they almost always have a second tank holding Gasoline which is used for cold starts. Something to keep in mind.
- Fuel economy is always lower. I'm not talking about hacked together conversions here: The same car you can buy in South America with the exact same engine will make slightly more power and get slightly less fuel economy with Ethanol... Alcohol has a lower energy density, so you have to burn more of it to go the same distance... For example:
Uno Mille 14,3 km/l Gasoline, 10,1 km/l Ethanol
VW Golf 1.6 (13,6 km/l Gasoline, 9,3 km/l Ethanol
These aren't poor tunes or flex fuel vehicles: These are factory vehicles developed and optimized for either fuel, specifically.
Etc...
I don't have a lot of experience with conversions but a lot of the Alternative Fuels research I am currently doing for my employer is centered around more efficient Ethanol combustion, so this is a topic I'm very interested in. I've got a good sized library of books on the subject (that I need to get around to reading more of one of these days
)
Last edited by PowerLabs; Jan 17, 2009 at 11:56 AM.
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Pro
Joined: May 2005
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From: The Woodlands TX
For arguments sake I will say it equals the economy of gas only if taking into account the drop in cost associated with its use but the reality is that although the MPG is lower by 10-15% the fuel costs 20+% less and thus is better economy by dollar cost vs miles driven.
Last edited by UberR32; Jan 17, 2009 at 12:55 PM.
Moderator
Joined: Dec 2002
Posts: 40,846
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From: Lakewood Ranch, FL
Cornell and Cal Berkley study on the energy cost of Bio fuels.
Drifting
Joined: Feb 2006
Posts: 1,531
Likes: 0
From: Deerfield Beach FL
Checked the chart and the nearest E85 station is 30 miles away, too far at this time to make it worth the round trip. When it becomes more widely available I will look into this.
Thanks for the write-up, it's another option to consider.
Thanks for the write-up, it's another option to consider.
Melting Slicks
Joined: Mar 2008
Posts: 2,835
Likes: 5
From: Avon Park FLORIDA
St. Jude Donor '08-'09-'10
Did you check the link I provided for finding a next nearest location?
Here is the link from above:
http://www.e85refueling.com/
Here is the link from above:
http://www.e85refueling.com/
thanks
they are expanding coverage, maybe soon.
Tech Contributor
Joined: Jul 2002
Posts: 14,949
Likes: 262
From: St. Louis, MO
St. Jude Donor '08
Some heavy duty drag racers I know back in St. Louis swear by alcohol as it made their car very consistent in heat or cold on the dragstrip (St. Louis has wide variations in temperature 30 degrees in a day is not uncommon).
I wonder if alcohol would help my drag strip performance in the heat down here?
hmmm....a set of AFR's milled to give 12.5 compression...flycut the bejesus out of my pistons....new injectors...the fun of doing more tuning.....
Melting Slicks
Joined: Aug 2006
Posts: 2,167
Likes: 11
From: Powell TN
Cruise-In VIII Veteran
I have a few questions I've always been curious about.
What will you use to read AFR?
Most widebands read between 10-20 afr, which won't even read the stoich afr of 9.7:1 for E85. Some will read down into the lower 8s, which would work for stoich, but not for a PE as rich as 6 or 7.
Do flex fuel cars have wideband sensors in them?
If not wideband sensors, how do the 02 sensors work to keep the afr at 9.7 when they only read accurately in the ~14 to 15 range?
A few "things to know" about ethanol.
Ethanol is moonshine. I wonder if you can get away with building your own still and say that you are making ethanol for, um, you know, the trees. I have some peach, blackberry, and mango "ethanol" in the fridge downstairs. 
The only difference in it and ethanol is a little gas is added to the ethanol to make it undrinkable.
Ethanol, as is any alcohol, is corrosive. Much less than other alcohols, but is still harmful over time. For some reason, a lot of European based vehicles in the US have had issues with ethanol causing fuel pump failures.
Ethanol absorbs water. All the older guys remember using alcohol to remove water from gas tanks. For this reason and the corrosiveness, alcohol is not able to be transported through conventional pipelines. It is only added to the tanker truck just before delivery to the gas station. This doesn't solve the problem of water absorption in the underground tanks. Also, a lot of Corvettes are susceptible to this, since they tend to sit for long periods of time. If enough water (condensation) is present this will result in two layers of liquid. The top layer would be gas, with a lower ethanol content (depending upon how much absorbed with water), and the lower layer would be a 75% ethanol, 25% water mix, which is not combustible. This would be the first thing the fuel pump picks up. This problem is more prevalent with boats running ethanol mix.
Because of the less energy producing nature of ethanol, a vehicle would have to run a compression ratio of about 20:1 to become as fuel efficient as a gasoline engine. This would only be practical for an "ethanol only" vehicle, not for flex fuel.
I don't have proof of this, but it makes sense. 91 octane E10 fuel is 89 octane fuel with ethanol added. The higher octane of the ethanol boosts the octane rating from 89 to 91. So you end up paying 10 to 15 cents a gallon more for 90% of a lower grade of fuel that is cut with 10% of a fuel that lowers fuel mileage and can potentially corrode parts.
What will you use to read AFR?
Most widebands read between 10-20 afr, which won't even read the stoich afr of 9.7:1 for E85. Some will read down into the lower 8s, which would work for stoich, but not for a PE as rich as 6 or 7.
Do flex fuel cars have wideband sensors in them?
If not wideband sensors, how do the 02 sensors work to keep the afr at 9.7 when they only read accurately in the ~14 to 15 range?
A few "things to know" about ethanol.
Ethanol is moonshine.
I wonder if you can get away with building your own still and say that you are making ethanol for, um, you know, the trees. I have some peach, blackberry, and mango "ethanol" in the fridge downstairs. The only difference in it and ethanol is a little gas is added to the ethanol to make it undrinkable.Ethanol, as is any alcohol, is corrosive. Much less than other alcohols, but is still harmful over time. For some reason, a lot of European based vehicles in the US have had issues with ethanol causing fuel pump failures.
Ethanol absorbs water. All the older guys remember using alcohol to remove water from gas tanks. For this reason and the corrosiveness, alcohol is not able to be transported through conventional pipelines. It is only added to the tanker truck just before delivery to the gas station. This doesn't solve the problem of water absorption in the underground tanks. Also, a lot of Corvettes are susceptible to this, since they tend to sit for long periods of time. If enough water (condensation) is present this will result in two layers of liquid. The top layer would be gas, with a lower ethanol content (depending upon how much absorbed with water), and the lower layer would be a 75% ethanol, 25% water mix, which is not combustible. This would be the first thing the fuel pump picks up. This problem is more prevalent with boats running ethanol mix.
Because of the less energy producing nature of ethanol, a vehicle would have to run a compression ratio of about 20:1 to become as fuel efficient as a gasoline engine. This would only be practical for an "ethanol only" vehicle, not for flex fuel.
I don't have proof of this, but it makes sense. 91 octane E10 fuel is 89 octane fuel with ethanol added. The higher octane of the ethanol boosts the octane rating from 89 to 91. So you end up paying 10 to 15 cents a gallon more for 90% of a lower grade of fuel that is cut with 10% of a fuel that lowers fuel mileage and can potentially corrode parts.
Melting Slicks
Joined: Oct 2000
Posts: 2,235
Likes: 65
From: Herndon VA
Thank you for sharing real life experience.
All of the test cars produced more power by virtue of the cooling effect of the IAT's and reduced detonation with its higher octane. Any and all Properly tuned vehicles will produce more power. You are correct that the fuel itself doesnt produce more power by volume burned.
Yes, that's what I think I said in my original post.
I was very clear in stating that it must be "tuned for its use" and that includes spark optimization and leaning out the vehicle where it gains its economy by its lean PE fueling. A purpose built motor using E85 can be as efficient or more so if the fuel's qualities are all expolited. Compression is a major fuel economy component that isnt used in a retune like this.
I don't think I would count fuel savings under PE in fuel economy. Again, you will see at least a 20% decrese in mpg. Here, E85 is about 10-20% cheaper which is consistent with what it was in Indy. Dollar per mile is roughly the same or worse, again, your location may vary based on the corn belt. Of course, even if that's true, the performanec is worth the extra cost.
For arguments sake I will say it equals the economy of gas only if taking into account the drop in cost associated with its use but the reality is that although the MPG is lower by 10-15% the fuel costs 20+% less and thus is better economy by dollar cost vs miles driven.
I assumed we were talking mpg, not $/mile. $/mile, again, works about to be the same or a little worse, but really depends on your location. I've seen places where E85 is more than gas.
I would very much like to see a sharing of the actual tuning if you feel so inclined. I'm sure I can piece it together with no help but its nice to see a colaboration. If not, I understand trade secrets if its an income for you.
All of the test cars produced more power by virtue of the cooling effect of the IAT's and reduced detonation with its higher octane. Any and all Properly tuned vehicles will produce more power. You are correct that the fuel itself doesnt produce more power by volume burned.
Yes, that's what I think I said in my original post.
I was very clear in stating that it must be "tuned for its use" and that includes spark optimization and leaning out the vehicle where it gains its economy by its lean PE fueling. A purpose built motor using E85 can be as efficient or more so if the fuel's qualities are all expolited. Compression is a major fuel economy component that isnt used in a retune like this.
I don't think I would count fuel savings under PE in fuel economy. Again, you will see at least a 20% decrese in mpg. Here, E85 is about 10-20% cheaper which is consistent with what it was in Indy. Dollar per mile is roughly the same or worse, again, your location may vary based on the corn belt. Of course, even if that's true, the performanec is worth the extra cost.
For arguments sake I will say it equals the economy of gas only if taking into account the drop in cost associated with its use but the reality is that although the MPG is lower by 10-15% the fuel costs 20+% less and thus is better economy by dollar cost vs miles driven.
I assumed we were talking mpg, not $/mile. $/mile, again, works about to be the same or a little worse, but really depends on your location. I've seen places where E85 is more than gas.
I would very much like to see a sharing of the actual tuning if you feel so inclined. I'm sure I can piece it together with no help but its nice to see a colaboration. If not, I understand trade secrets if its an income for you.
Safety Car
Joined: Oct 2001
Posts: 4,945
Likes: 0
From: Dallas/Valley Ranch TEXAS!!!
Melting Slicks
Joined: Oct 2000
Posts: 2,235
Likes: 65
From: Herndon VA
Most of the stations I saw would vary with the cost of gas. It doesn't seem right to me. Meijer kept their E85 $0.40 cheaper than 87 when it was $4.00.
Melting Slicks
Joined: Oct 2000
Posts: 2,235
Likes: 65
From: Herndon VA
Very true. Most of the time, I saw E70 at the pumps so we actually tuned for E70 which runs at roughly 10.7:1.
Melting Slicks
Joined: Oct 2000
Posts: 2,235
Likes: 65
From: Herndon VA
I have a few questions I've always been curious about.
What will you use to read AFR?
Most widebands read between 10-20 afr, which won't even read the stoich afr of 9.7:1 for E85. Some will read down into the lower 8s, which would work for stoich, but not for a PE as rich as 6 or 7.
Do flex fuel cars have wideband sensors in them?
If not wideband sensors, how do the 02 sensors work to keep the afr at 9.7 when they only read accurately in the ~14 to 15 range?
O2 sensors actually read lambda, not AFR, so 9.7:1 E85 = 1 lambda = 14.7:1 gas. I actually tune using lambda, not AFR, but you can "think" in gas AFR's if that helps.
A few "things to know" about ethanol.
Ethanol is moonshine. I wonder if you can get away with building your own still and say that you are making ethanol for, um, you know, the trees. I have some peach, blackberry, and mango "ethanol" in the fridge downstairs. The only difference in it and ethanol is a little gas is added to the ethanol to make it undrinkable.
Ethanol, as is any alcohol, is corrosive. Much less than other alcohols, but is still harmful over time. For some reason, a lot of European based vehicles in the US have had issues with ethanol causing fuel pump failures.
Ethanol absorbs water. All the older guys remember using alcohol to remove water from gas tanks. For this reason and the corrosiveness, alcohol is not able to be transported through conventional pipelines. It is only added to the tanker truck just before delivery to the gas station. This doesn't solve the problem of water absorption in the underground tanks. Also, a lot of Corvettes are susceptible to this, since they tend to sit for long periods of time. If enough water (condensation) is present this will result in two layers of liquid. The top layer would be gas, with a lower ethanol content (depending upon how much absorbed with water), and the lower layer would be a 75% ethanol, 25% water mix, which is not combustible. This would be the first thing the fuel pump picks up. This problem is more prevalent with boats running ethanol mix.
Because of the less energy producing nature of ethanol, a vehicle would have to run a compression ratio of about 20:1 to become as fuel efficient as a gasoline engine. This would only be practical for an "ethanol only" vehicle, not for flex fuel.
I don't have proof of this, but it makes sense. 91 octane E10 fuel is 89 octane fuel with ethanol added. The higher octane of the ethanol boosts the octane rating from 89 to 91. So you end up paying 10 to 15 cents a gallon more for 90% of a lower grade of fuel that is cut with 10% of a fuel that lowers fuel mileage and can potentially corrode parts.
What will you use to read AFR?
Most widebands read between 10-20 afr, which won't even read the stoich afr of 9.7:1 for E85. Some will read down into the lower 8s, which would work for stoich, but not for a PE as rich as 6 or 7.
Do flex fuel cars have wideband sensors in them?
If not wideband sensors, how do the 02 sensors work to keep the afr at 9.7 when they only read accurately in the ~14 to 15 range?
O2 sensors actually read lambda, not AFR, so 9.7:1 E85 = 1 lambda = 14.7:1 gas. I actually tune using lambda, not AFR, but you can "think" in gas AFR's if that helps.
A few "things to know" about ethanol.
Ethanol is moonshine.
I wonder if you can get away with building your own still and say that you are making ethanol for, um, you know, the trees. I have some peach, blackberry, and mango "ethanol" in the fridge downstairs. The only difference in it and ethanol is a little gas is added to the ethanol to make it undrinkable.Ethanol, as is any alcohol, is corrosive. Much less than other alcohols, but is still harmful over time. For some reason, a lot of European based vehicles in the US have had issues with ethanol causing fuel pump failures.
Ethanol absorbs water. All the older guys remember using alcohol to remove water from gas tanks. For this reason and the corrosiveness, alcohol is not able to be transported through conventional pipelines. It is only added to the tanker truck just before delivery to the gas station. This doesn't solve the problem of water absorption in the underground tanks. Also, a lot of Corvettes are susceptible to this, since they tend to sit for long periods of time. If enough water (condensation) is present this will result in two layers of liquid. The top layer would be gas, with a lower ethanol content (depending upon how much absorbed with water), and the lower layer would be a 75% ethanol, 25% water mix, which is not combustible. This would be the first thing the fuel pump picks up. This problem is more prevalent with boats running ethanol mix.
Because of the less energy producing nature of ethanol, a vehicle would have to run a compression ratio of about 20:1 to become as fuel efficient as a gasoline engine. This would only be practical for an "ethanol only" vehicle, not for flex fuel.
I don't have proof of this, but it makes sense. 91 octane E10 fuel is 89 octane fuel with ethanol added. The higher octane of the ethanol boosts the octane rating from 89 to 91. So you end up paying 10 to 15 cents a gallon more for 90% of a lower grade of fuel that is cut with 10% of a fuel that lowers fuel mileage and can potentially corrode parts.