E85 + tuned for 93 octane = boom?
Update. Please don't assume I didn't have a clue to what E85 is and just decided to fill up on it to save money. I know gasoline has more energy than alcohol which is why you would get less mileage due to more ethanol being needed for proper combustion. I was assuming the ecu would add more fuel and my gas mileage would just suffer. Why even put E85 in you ask? I thought it was like race gas where you just fill up and turn up the boost. Where did I get this idea? I read that ethanol is 105 octane. Bad idea to say at the very least. What's going on with the car right now? I drove it on the highway for awhile and after that filled up with V-power. It's roughly half e85 and half premium gas. I will continue to take it easy until I can get rid it and reset the ecu after that. Thanks to all who actually had something helpful to say.
It's no wonder our insurance rates go through the roof because these same people are wondering...."can I take this corner at 80mph? I read it online and it said the evo can do it!"
Idiots .....
^^^
Here is my E85 stock injector (downsized to 325) fuel map. I've had 5k miles of E85 @ 20psi on my 03 stock injectors.
Here is my E85 stock injector (downsized to 325) fuel map. I've had 5k miles of E85 @ 20psi on my 03 stock injectors.
Last edited by Jeff_Jeske; Feb 7, 2008 at 01:30 PM.
And because I'm feeling generous... here is the timing map I use.
I've even tracked the car with these maps but fuel consumption is too high making it a PITA during lapping days.
I've even tracked the car with these maps but fuel consumption is too high making it a PITA during lapping days.
Last edited by Jeff_Jeske; Oct 20, 2007 at 10:57 AM.
His numbers are relative to the numbers in the table, not the actual AFR's.. Tuning with a gasoline calibrated wideband will read what you'd expect for GASOLINE, so 12.0 isn't unreasonable.
Basically, he used smaller injector setting which increased the duty cycle globally, in doing that, its getting more fuel (roughly 30% more according to the size he chose) but the open loop maps on a wideband would be too rich, so he had to lean out the map slightly to hit his target..
14.7 is stoich, lambda 1.0 for gasoline, E85 is I think 8.5 however its also 1.0lambda.. if you tune a E85 car with a gasoline calibrated wideband, stoich will be 14.7 according to the GASOLINE calibration.
This is just a pretty confusing topic.. But there's enough bad information in this thread to warrant my post.
I wouldn't obviously use any of the maps posted here, and get a custom tune for E85, but I wanted to point out that the methodology of what was done, wasn't incorrect.
In the future, its important to point out that most widebands are calibrated for gasoline, therefore its important to clarify that. If you were to tune an E85 car, on an Ethanol calibrated wideband, then 12.0 would blow up the engine.
To answer the original post, the car is effectively going to run too lean with E85 on a stock Evo tune, because E85 requires roughly 30% more fuel to run "equivalently" to gasoline. Your best option is to drain the E85 and put in gasoline, if you cannot do that, then your taking a chance doing damage when the car drops out of closed loop. Obviously a tune just to accomodate a mistake isn't such a great idea, and its strongly suggested you just drain the tank before you do damage.
Our cars are not flex fuel capable, and cannot accomodate the fueling changes required to adapt to E85 without a special tune, its one or the other.. So we can leave it at that.
I also wanted to add that the fuel system, and everything else in the car is capable of running E85 without detriment, e85 is corrosive, but not likely enough to do damage to a modern fuel system. E85 will absorb moisture and it acts as a detergent, so sludge and other crud that accumulates in the tank and fuel system will get cleaned out and you'll have to change your fuel filter, on some high mileage cars, it can also gum up the fuel pump and it might need to be changed.
The only thing preventing most cars built after 1995 from running E85, is a tune for it.. For some cars, its as easy as swapping in a set of 30% larger injectors and making very minor adjustments..
You made a mistake.. Thats okay.. Fix it before you make a bigger headache for yourself and you'll be fine.
Basically, he used smaller injector setting which increased the duty cycle globally, in doing that, its getting more fuel (roughly 30% more according to the size he chose) but the open loop maps on a wideband would be too rich, so he had to lean out the map slightly to hit his target..
14.7 is stoich, lambda 1.0 for gasoline, E85 is I think 8.5 however its also 1.0lambda.. if you tune a E85 car with a gasoline calibrated wideband, stoich will be 14.7 according to the GASOLINE calibration.
This is just a pretty confusing topic.. But there's enough bad information in this thread to warrant my post.
I wouldn't obviously use any of the maps posted here, and get a custom tune for E85, but I wanted to point out that the methodology of what was done, wasn't incorrect.
In the future, its important to point out that most widebands are calibrated for gasoline, therefore its important to clarify that. If you were to tune an E85 car, on an Ethanol calibrated wideband, then 12.0 would blow up the engine.
To answer the original post, the car is effectively going to run too lean with E85 on a stock Evo tune, because E85 requires roughly 30% more fuel to run "equivalently" to gasoline. Your best option is to drain the E85 and put in gasoline, if you cannot do that, then your taking a chance doing damage when the car drops out of closed loop. Obviously a tune just to accomodate a mistake isn't such a great idea, and its strongly suggested you just drain the tank before you do damage.
Our cars are not flex fuel capable, and cannot accomodate the fueling changes required to adapt to E85 without a special tune, its one or the other.. So we can leave it at that.
I also wanted to add that the fuel system, and everything else in the car is capable of running E85 without detriment, e85 is corrosive, but not likely enough to do damage to a modern fuel system. E85 will absorb moisture and it acts as a detergent, so sludge and other crud that accumulates in the tank and fuel system will get cleaned out and you'll have to change your fuel filter, on some high mileage cars, it can also gum up the fuel pump and it might need to be changed.
The only thing preventing most cars built after 1995 from running E85, is a tune for it.. For some cars, its as easy as swapping in a set of 30% larger injectors and making very minor adjustments..
You made a mistake.. Thats okay.. Fix it before you make a bigger headache for yourself and you'll be fine.
Last edited by MalibuJack; Oct 20, 2007 at 03:46 PM.
Malibu jack, with all respect for you 12 afr on a gas reading wideband is too lean. E85 stoich is 9.87 lambda you are right, I forget off hand what the max lean for producing power on it is ... Let's say 0.75 lambda. If u have a gas reading wideband that transfers to about 11 afr or so .
So again 12 on a gas equivalent WB is too lean, he might get away with it because he runs low boost but also just because he has it in his map it doesn't even mean he actually runs 12.
So again 12 on a gas equivalent WB is too lean, he might get away with it because he runs low boost but also just because he has it in his map it doesn't even mean he actually runs 12.
Last edited by mplspilot; Oct 20, 2007 at 03:50 PM.
Its not too lean, its an academic argument for the purpose of this thread as its not relevent to this specific OP's question. But you can run E85 "leaner" than gasoline because of the properties of alchol and higher relative octane. You are right though, better safe than sorry until more good knowledge about E85 propegates.
I do understand your point though, and for most, comparing apples to apples, yes, you would run it a bit richer. But I also have seen *MANY* gasoline tunes from tuners running 12.0.. So go figure eh?
I usually tune with both a wideband and EGT sensor, and there are many cases where you can run leaner than the "common knowledge" would suggest. But like anything else, it depends on EGT, Knock resistence of your engine, etc. Ethanol is a weird animal to tune, but it also rewards when done right.
I just can't wait until I am somewhere I have easy access to it, instead of doing the rare experimenting when I can get a 55 gallon drum delivered.
I do understand your point though, and for most, comparing apples to apples, yes, you would run it a bit richer. But I also have seen *MANY* gasoline tunes from tuners running 12.0.. So go figure eh?
I usually tune with both a wideband and EGT sensor, and there are many cases where you can run leaner than the "common knowledge" would suggest. But like anything else, it depends on EGT, Knock resistence of your engine, etc. Ethanol is a weird animal to tune, but it also rewards when done right.
I just can't wait until I am somewhere I have easy access to it, instead of doing the rare experimenting when I can get a 55 gallon drum delivered.
well academically there's no point running leaner than max lean for any given fuel. All that's gonna be accomplished is loss of power and more chances of detonation. What I'm saying thou is go ahead and do what u like, don't suggest that other people do it.
Low 11 should be run on gas wb on e85 to make power and stay safe.
Low 11 should be run on gas wb on e85 to make power and stay safe.
well academically there's no point running leaner than max lean for any given fuel. All that's gonna be accomplished is loss of power and more chances of detonation. What I'm saying thou is go ahead and do what u like, don't suggest that other people do it.
Low 11 should be run on gas wb on e85 to make power and stay safe.
Low 11 should be run on gas wb on e85 to make power and stay safe.
Max power lean for E85 is 0.8673 lambda, which is over 12:1 on a gasoline calibrated wideband. You are correct that there is no point in running leaner than max lean, but you are incorrect on where that point is.
-Paul
I think it's fine to run E85 somewhat rich, I did 380whp on a dyno dynamics today running around 11afr, don't really see a whole lot of reason to go real lean even if you might be able to get away with it
Thanks Paul, I knew I didn't remember it correctly
But continuing with my thought, would anybody actually even want to run max lean?? Do we run max lean on gasoline, which is what, 12.5? Nope, I don't think anybody's doing it... Shouldn't the same logic be applied to e85
Merkzu, hey nice numbers today! Still stock turbo, right?
Actually my bad, max lean for gas is like 13.2 or so. 12.5 is max rich. So we run gasoline richer than max rich and you guys offer to run e85 leaner than max lean. Something is wrong with this thought dont you think??
AFAIK a good quality of e85 is that it will make good torque at richer ratios from stoich than gasoline.
AFAIK a good quality of e85 is that it will make good torque at richer ratios from stoich than gasoline.
Last edited by mplspilot; Oct 20, 2007 at 06:41 PM.