May have solved 100% E85 on LNF puzzle
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From: Seattle, WA
Yes. It will be especially useful for big turbo setups.
I can't speak with much experience on the numbers here, but in general E85 allows more timing advance which helps make more power. There's others that have run 50/50 E85 and had great results.
Last edited by VinceTrifecta; Mar 7, 2011 at 11:12 PM. Reason: Automerged Doublepost
Well if this works, I may be getting a TF/HP tune combo in the near future, gotta start sourcing out E85 stations in the area, if I can find them, don't seem to be many in Ohio. Vince, think a switchable E85/93 tune would be possible? That's be probably the best solution possible.
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From: Carlsbad, CA
1) it is an alcohol based fuel that hold less specific energy than normal gasoline, which means you have to run richer, which is fine because...
2) it is an alcohol base so it has an extra oxygen molecule attached to the molecular chain more Oxygen in the cylinders means more thermal expansion mean MORE POWA!!!
3) it is much more knock resistant and can handle more boost
5) it will let you pass smog with no smog emissions controls... unless you have a **** doing the visual inspection.
6) it smells like you are burning a still full of moonshine.
As a note, in my opinion people that are doing this for the LNF in order to get more fuel economy are doing it for the wrong reasons. You use more E85 than premium even though you are paying less for it. 30hp for a few miles/gallon less and a few cents less at the pump is a very worthy trade off.
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Joined: 04-09-08
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From: Seattle, WA
Update
100% E85 test was a success!
I drained my HHR SS down to 1/2 gallon, filled up with E85. Tuned for stoich changes, and tried running 24psi boost on stock injection timing and stock fuel rail pressure. I hit injector window misfire badly.
Advanced injection timing to 320* (STOCK rail pressure), tested again, car pulled like a freight train all the way to 7000 RPM. In fact, there may be some benefits to running advanced injection timing even on gasoline. I also had some subtle reminders that my clutch is iffy at best. Lol
Spent a few hours driving the car around, towards the end of the night it seemed like it might have started having issues with misfire again as it was getting colder outside, so fuel demands were climbing. Avg. economy was mid 24s - not bad considering I wasn't exactly babying the car.
The only other issue I ran into is I ran my low pressure pump past its limit - I did one 1st through 4th gear pull (NLSing from 3rd to 4th) and at around 5000RPM or so, the power dropped, then it said ENG PWR REDUCED, and set a P0087 code (low rail pressure).
I was seeing injector pulsewidth up to 12ms with no problems.
I'm going to work with a couple other people to test these injection timing changes over the next few days, but this should be ready very soon.
100% E85 test was a success!
I drained my HHR SS down to 1/2 gallon, filled up with E85. Tuned for stoich changes, and tried running 24psi boost on stock injection timing and stock fuel rail pressure. I hit injector window misfire badly.
Advanced injection timing to 320* (STOCK rail pressure), tested again, car pulled like a freight train all the way to 7000 RPM. In fact, there may be some benefits to running advanced injection timing even on gasoline. I also had some subtle reminders that my clutch is iffy at best. Lol
Spent a few hours driving the car around, towards the end of the night it seemed like it might have started having issues with misfire again as it was getting colder outside, so fuel demands were climbing. Avg. economy was mid 24s - not bad considering I wasn't exactly babying the car.
The only other issue I ran into is I ran my low pressure pump past its limit - I did one 1st through 4th gear pull (NLSing from 3rd to 4th) and at around 5000RPM or so, the power dropped, then it said ENG PWR REDUCED, and set a P0087 code (low rail pressure).
I was seeing injector pulsewidth up to 12ms with no problems.
I'm going to work with a couple other people to test these injection timing changes over the next few days, but this should be ready very soon.
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Joined: 10-13-10
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From: Washougal, WA
5) it will let you pass smog with no smog emissions controls... unless you have a **** doing the visual inspection.
6) it smells like you are burning a still full of moonshine.
This is worth it alone!!!
6) it smells like you are burning a still full of moonshine.
This is worth it alone!!!
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Joined: 07-23-10
Posts: 3,451
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From: Carlsbad, CA
Update
100% E85 test was a success!
I drained my HHR SS down to 1/2 gallon, filled up with E85. Tuned for stoich changes, and tried running 24psi boost on stock injection timing and stock fuel rail pressure. I hit injector window misfire badly.
Advanced injection timing to 320* (STOCK rail pressure), tested again, car pulled like a freight train all the way to 7000 RPM. In fact, there may be some benefits to running advanced injection timing even on gasoline. I also had some subtle reminders that my clutch is iffy at best. Lol
Spent a few hours driving the car around, towards the end of the night it seemed like it might have started having issues with misfire again as it was getting colder outside, so fuel demands were climbing. Avg. economy was mid 24s - not bad considering I wasn't exactly babying the car.
The only other issue I ran into is I ran my low pressure pump past its limit - I did one 1st through 4th gear pull (NLSing from 3rd to 4th) and at around 5000RPM or so, the power dropped, then it said ENG PWR REDUCED, and set a P0087 code (low rail pressure).
I was seeing injector pulsewidth up to 12ms with no problems.
I'm going to work with a couple other people to test these injection timing changes over the next few days, but this should be ready very soon.
100% E85 test was a success!
I drained my HHR SS down to 1/2 gallon, filled up with E85. Tuned for stoich changes, and tried running 24psi boost on stock injection timing and stock fuel rail pressure. I hit injector window misfire badly.
Advanced injection timing to 320* (STOCK rail pressure), tested again, car pulled like a freight train all the way to 7000 RPM. In fact, there may be some benefits to running advanced injection timing even on gasoline. I also had some subtle reminders that my clutch is iffy at best. Lol
Spent a few hours driving the car around, towards the end of the night it seemed like it might have started having issues with misfire again as it was getting colder outside, so fuel demands were climbing. Avg. economy was mid 24s - not bad considering I wasn't exactly babying the car.
The only other issue I ran into is I ran my low pressure pump past its limit - I did one 1st through 4th gear pull (NLSing from 3rd to 4th) and at around 5000RPM or so, the power dropped, then it said ENG PWR REDUCED, and set a P0087 code (low rail pressure).
I was seeing injector pulsewidth up to 12ms with no problems.
I'm going to work with a couple other people to test these injection timing changes over the next few days, but this should be ready very soon.
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Joined: 04-09-08
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From: Seattle, WA
That can't really be done on the LNF because there's no way for the ECM to determine how much ethanol is in the tank. You could run two different tunes, but you'd have to make sure the tank was as close to empty as possible before switching fueling (and you'd have to switch the tune).
I may put a feature into EZ Flash so end customers can make adjustments for any mix of E85
I may put a feature into EZ Flash so end customers can make adjustments for any mix of E85
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Joined: 04-09-08
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From: Seattle, WA
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I have a question...
Has anyone shown conclusive benefit to increasing the ethanol percentage over say 50%? There have been a few studies done on ethanol and compression ratio, mpg, timing, kr and power output and it seems to me they were finding diminishing returns on mixes over as low as 30-40% ethanol. Several of the studies were even done using the LNF engines. Basic findings (that I can remember) are that the LNF is most definitely "knock limited" on pump gas, which we already knew. This means there's no way you can get to MBT on 91 octane fuel. MBT I believe was reached with far less than 100% ethanol, I think it might have been below 50% even.
Fuel mileage had similar findings, highest mpg was reached not at straight pump gas, but at somewhere around 20-30% ethanol. This obviously was because of being able to run more timing, but once you're at the timing that would give the best mpg, and the octane to keep kr at bay, there is no reason or need to go higher on ethanol to reduce knock.
Sooooo, my question is like I said, has anyone shown that E85 makes more power than say E48 in the LNF? I know mpg's will keep going down over 50% or so, but I know that's not what most of us are looking for here. My personal experience, gathered information and my own testing has led me to believe between 35% and 55% ethanol is all that's needed to make good power and decent efficiency. The engineers, professors and engineering students that put those studies together seemed to say the same thing. I believe it's just like octane, you only want as much as you need to control kr, and no more. Raising octane levels higher than needed creates less power.
Has anyone shown conclusive benefit to increasing the ethanol percentage over say 50%? There have been a few studies done on ethanol and compression ratio, mpg, timing, kr and power output and it seems to me they were finding diminishing returns on mixes over as low as 30-40% ethanol. Several of the studies were even done using the LNF engines. Basic findings (that I can remember) are that the LNF is most definitely "knock limited" on pump gas, which we already knew. This means there's no way you can get to MBT on 91 octane fuel. MBT I believe was reached with far less than 100% ethanol, I think it might have been below 50% even.
Fuel mileage had similar findings, highest mpg was reached not at straight pump gas, but at somewhere around 20-30% ethanol. This obviously was because of being able to run more timing, but once you're at the timing that would give the best mpg, and the octane to keep kr at bay, there is no reason or need to go higher on ethanol to reduce knock.
Sooooo, my question is like I said, has anyone shown that E85 makes more power than say E48 in the LNF? I know mpg's will keep going down over 50% or so, but I know that's not what most of us are looking for here. My personal experience, gathered information and my own testing has led me to believe between 35% and 55% ethanol is all that's needed to make good power and decent efficiency. The engineers, professors and engineering students that put those studies together seemed to say the same thing. I believe it's just like octane, you only want as much as you need to control kr, and no more. Raising octane levels higher than needed creates less power.
Thread Starter
Member
Joined: 04-09-08
Posts: 377
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From: Seattle, WA
I have a question...
Has anyone shown conclusive benefit to increasing the ethanol percentage over say 50%? There have been a few studies done on ethanol and compression ratio, mpg, timing, kr and power output and it seems to me they were finding diminishing returns on mixes over as low as 30-40% ethanol. Several of the studies were even done using the LNF engines. Basic findings (that I can remember) are that the LNF is most definitely "knock limited" on pump gas, which we already knew. This means there's no way you can get to MBT on 91 octane fuel. MBT I believe was reached with far less than 100% ethanol, I think it might have been below 50% even.
Fuel mileage had similar findings, highest mpg was reached not at straight pump gas, but at somewhere around 20-30% ethanol. This obviously was because of being able to run more timing, but once you're at the timing that would give the best mpg, and the octane to keep kr at bay, there is no reason or need to go higher on ethanol to reduce knock.
Sooooo, my question is like I said, has anyone shown that E85 makes more power than say E48 in the LNF? I know mpg's will keep going down over 50% or so, but I know that's not what most of us are looking for here. My personal experience, gathered information and my own testing has led me to believe between 35% and 55% ethanol is all that's needed to make good power and decent efficiency. The engineers, professors and engineering students that put those studies together seemed to say the same thing. I believe it's just like octane, you only want as much as you need to control kr, and no more. Raising octane levels higher than needed creates less power.
Has anyone shown conclusive benefit to increasing the ethanol percentage over say 50%? There have been a few studies done on ethanol and compression ratio, mpg, timing, kr and power output and it seems to me they were finding diminishing returns on mixes over as low as 30-40% ethanol. Several of the studies were even done using the LNF engines. Basic findings (that I can remember) are that the LNF is most definitely "knock limited" on pump gas, which we already knew. This means there's no way you can get to MBT on 91 octane fuel. MBT I believe was reached with far less than 100% ethanol, I think it might have been below 50% even.
Fuel mileage had similar findings, highest mpg was reached not at straight pump gas, but at somewhere around 20-30% ethanol. This obviously was because of being able to run more timing, but once you're at the timing that would give the best mpg, and the octane to keep kr at bay, there is no reason or need to go higher on ethanol to reduce knock.
Sooooo, my question is like I said, has anyone shown that E85 makes more power than say E48 in the LNF? I know mpg's will keep going down over 50% or so, but I know that's not what most of us are looking for here. My personal experience, gathered information and my own testing has led me to believe between 35% and 55% ethanol is all that's needed to make good power and decent efficiency. The engineers, professors and engineering students that put those studies together seemed to say the same thing. I believe it's just like octane, you only want as much as you need to control kr, and no more. Raising octane levels higher than needed creates less power.
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From: Carlsbad, CA
Sweet baby jeebus... If thats all it takes I might be one of your first customers. Thats alot of fuel moving up the lines too... damn 255 liters per hour haha wow
