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Old 09-07-2005, 08:13 PM   #76
icantdrive75
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Wow...almost a dollar less...that's nuts. I need that in Texas.
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Old 09-07-2005, 11:40 PM   #77
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well i started to blend today, but the price at the one station that carries in it colorado springs has it for 3.09 a gallon, which is exactly the same price as mid grade 87.

first impressions, not much, taking it easy for now, car seams to run good on it so far. i mixed 3 gallons in a full tank, which works out to around 18-19%. i will ease up to around 30% over the next few tanks.
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Old 09-08-2005, 01:29 AM   #78
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wow, your midgrade is 87... that is our piss...and it's dropping, saw it for $2.89 today
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Old 09-08-2005, 05:23 PM   #79
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question for hotrod or anyone else. I drive a supercharged RSX. currently tuned for 14.7AFR closed loop and 12.0AFR in boost on 93 octane.

question #1: how would my tune change if I were to start blending in E85 or switch to E85 completely. i know i probably have to add about 27% more fuel across the board. I already have oversized fuel injectors.

you said that E85 stoich AFR is 9.7ish:1 My O2 sensor only reads to 10.48:1 AFR. would i need a totally new AF system like the AEM UEGO? the ECU targets 14.7:1 in closed loop, how does this affect it running on E85 which wants 9.7ish:1? I'd be running ultra lean whenever i'm cruising?

Question #2: you said that E85 max power AFR is 8-9:1 is this when N/A or boost? since N/A under load normally wants 13ish and boost normally wants 12ish.


question #3: what all might need to be checked for E85 compatibility? so far i've gathered fueling neck hose, fuel pump, fuel tank, seals, fuel line, injector o-rings,



question #4: my mechanic friend said that there is concern running E85 due to higher cylinder pressures and that my rods aren't made for it. since I'm already boosting a factory NA car, my rods are already being stressed. would it not be wise to do this then.



thanks for a great faq.
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Old 09-08-2005, 07:04 PM   #80
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Quote:
Originally Posted by hotrod
There is a web site dedicated to E85 !

http://e85.specialgreen.com/

Larry
I meant a good website
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Old 09-09-2005, 03:49 AM   #81
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Like you care. They'll never start pumping this stuff in TX...are you kidding???
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Old 09-09-2005, 04:08 AM   #82
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Quote:
question for hotrod or anyone else. I drive a supercharged RSX. currently tuned for 14.7AFR closed loop and 12.0AFR in boost on 93 octane.
Quote:
question #1: how would my tune change if I were to start blending in E85 or switch to E85 completely. i know i probably have to add about 27% more fuel across the board. I already have oversized fuel injectors.
Very little, the E85 likes about the same ignition advance as gasoline, so you can start tuning by just running the same advance and tweak it later. The E85 will tolerate more advance due to its high octane but it might be counter productive.

Quote:
you said that E85 stoich AFR is 9.7ish:1 My O2 sensor only reads to 10.48:1 AFR. would i need a totally new AF system like the AEM UEGO? the ECU targets 14.7:1 in closed loop, how does this affect it running on E85 which wants 9.7ish:1? I'd be running ultra lean whenever i'm cruising?
Your O2 sensor does not care, it actually measures Lambda / equivalence ratio and converts it to Lambda 1 = 14.7 for gasoline. stoich on gasoline will read the same as stoich on alcohol. If your O2 sensor does not allow you to switch to Lambda or equivalence ratio output simply multiply or divide by 1.5 to get the true AFR/ FAR

Quote:
Question #2: you said that E85 max power AFR is 8-9:1 is this when N/A or boost? since N/A under load normally wants 13ish and boost normally wants 12ish.
You'll see the same need to richen the mixture slightly for boosted applications on alcohol, so you will want to shoot for the rich side of the max power range. In reality, there is very little if any increase in power to be had by going leaner than the max power rich mixture. For example if you tune an NA engine for 12.5:1 AFR you will only gain about 1% in power by pushing to the 13:1 AFR's at great risk of melting the engine.

Quote:
question #3: what all might need to be checked for E85 compatibility? so far i've gathered fueling neck hose, fuel pump, fuel tank, seals, fuel line, injector o-rings,
In some cases the fuel tank itself, the plastic tanks some cars use may not like high alcohol fuels. Avoid lots of mixed metals in the fuel system like copper, steel, aluminum, etc. Try to stay with stainless steel, nickle plated brass, mild steel, or anodized aluminum if you can. That will practically eliminate any issue with elecrolytic corrosion even if you get some water in your fuel.

Absolutely avoid magnesium and zinc and if possible un-anodized aluminum. The first two especially can be very active in corrosion.


Quote:
question #4: my mechanic friend said that there is concern running E85 due to higher cylinder pressures and that my rods aren't made for it. since I'm already boosting a factory NA car, my rods are already being stressed. would it not be wise to do this then.
He is right in a theoretical sense, higher torque by definition means higher cylinder pressures. What most folks don't realize is that RPM is the biggest killer of con rods.
maximum stress on the con rods actually occurs as the rod passes TDC on the beginning of the intake stroke when suction forces during intake combine with inertial loads due to the rapid change in direction.

Alcohol produces higher mean cylinder pressures but much of that is due to a longer period of usable pressures, max pressure may actually be slightly lower than on gasoline.



Quote:
thanks for a great faq.
Your welcome --- glad folks are finding it interesting



Larry
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Old 09-09-2005, 02:12 PM   #83
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I think if we got together a lobby group in TX some independant stations might start pumping the stuff. I can get race gas (100 octane) at the pump pretty close to sherman

I have a few political connections I can start asking about if there is enough interest.
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Old 09-09-2005, 03:07 PM   #84
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WOULD THSI KILL MY CAR IF I MIXED IT, its a 93 legacy. ls, 2.2 n/a
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Old 09-09-2005, 04:42 PM   #85
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I would think you would see pretty much the same experience that hamfist has seen with his RS.

http://forums.nasioc.com/forums/showthread.php?t=796466

Larry
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Old 09-10-2005, 02:57 AM   #86
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You may have political connections...but oil companies have more...especially out here. They wouldn't allow something to steal their profits like that.

Quote:
Originally Posted by Milin
I think if we got together a lobby group in TX some independant stations might start pumping the stuff. I can get race gas (100 octane) at the pump pretty close to sherman

I have a few political connections I can start asking about if there is enough interest.
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Old 09-14-2005, 12:03 AM   #87
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Quote:
Originally Posted by icantdrive75
You may have political connections...but oil companies have more...especially out here. They wouldn't allow something to steal their profits like that.
unless they were selling it?

You DO live in oil central, TX though.

Tough to argue with a Mclaren and Enzo
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Old 09-14-2005, 03:06 PM   #88
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Quote:
Originally Posted by SpaceGhost
Well I read all this and some other threads on here. I went and and bought 8 gal of E85 to mix with the almost 8 Gallons of Shell 93. Drove for 10 miles. Then on the freeway opened her up. I didn't notice to much in performance, but since 93 was $2.89 a gallon and E85 was $2.34 I noticed a savings. I drove the rest of the way home, no cell lights not hesitation I even stopped by the local dealer to talke a look at the new 06 STI in person and then drove home. I have put 35 miles on the car in 93 degree heat and it is doing just fine. This is an 05 Cobb STG 1 STI. I am eager to see how many miles I can get out of the tank to see if I am really saving $4 a fill up. Thanks Hotrod for posting such valuable info!
Alright, from all the threads I have read, we seem to have one person that has tried it on a COBB stg 1 STI with good results. Has anyone tried this on a bone stock STI? SpaceGhost, could you switch to the base map and try it again? Please???
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Old 09-15-2005, 12:28 AM   #89
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Today in auto tech the teacher said he got a tax write off cause his ford CAN run ethanol...even tho he never would use that,"whatdyacallit?? that corn gas??" he says with a disgusted look on his face. Texas for you. I wonder if you could get a tax break for converting your car to run on E85. He said he got a 2k tax break...brake??? BRAIC!!!

That and I thought, a car that could run on ethanol and gasoline would be a hard contender in the Sport Compact Car USCC. With the E85 you'd have power and emissions, and with the gas you'd have good economy. Plus you'd get lots of points for engineering...
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Old 09-15-2005, 12:46 AM   #90
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you can actually get excellent gas mileage with ethanol, you just have to tune for it...
this is on a topic of heating fuel for vaporization for fuel efficiency for Formula SAE competition...aka a buddy of mine
"Heating fuel will increase efficency but decrease power.

I'd like to add a somewhat related example. It's amazing how different we set up our open cup engines vs. our restrictor plate engines. We try to run our restrictor pistons very hot which increases efficiency of the engine and since the air fuel mix is limited by the restrictor you can do more with less. But hot pistons heat the incoming air fuel charge reducing the volumetric effiency per cycle. So on an open engine big oil squirters are used to cool the piston and pick up VE, where power is limited by VE rather then the restrictor and thermal efficiency. It's amazing how many things I learned in college to increase the thermal efficiency of an engine actually reduce its output.

'engine and turbo guy'
Cornell 02-03

Production Engine Engineer Richard Childress Racing"
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Old 09-15-2005, 01:44 AM   #91
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I figured with such a richer stoich with E85 you'd get better mileage with gas.

Last edited by icantdrive75; 09-15-2005 at 02:38 AM. Reason: richer
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Old 09-15-2005, 02:27 AM   #92
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Homemade WRX --

Have the NASCAR teams started investigating engines optimized for E85 yet?
I've heard that there is talk of NASCAR also moving to fuel ethanol like the openwheel cars.

http://www.coloradocorn.com/news/ext...brownfield.htm

You know the more I think about it E85 in NASCAR would be the perfect marriage, not to mention an interesting twist of fate.

Junior Johnson probably already knows how to set up an engine to run ethanol

Quote:
you can actually get excellent gas mileage with ethanol, you just have to tune for it...
According to EPA pubs ethanol is capable of nearly doubling the engine effeciency of the internal combustion engine from the mid 20% range to about 41%.

That would require running about a 19:1 compression ratio though !!!

Larry

Last edited by hotrod; 09-15-2005 at 03:13 AM.
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Old 09-15-2005, 08:16 AM   #93
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no, nascar doesn't run E85...IRL is switching over to it though...

and my buddy runs 16.3:1 compression ratio in his carmen gia (or however you spell it)...so 19:1 isn't really all that big of a deal

Last edited by Homemade WRX; 09-15-2005 at 08:59 AM.
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Old 09-15-2005, 08:26 AM   #94
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Quote:
Originally Posted by hotrod
According to EPA pubs ethanol is capable of nearly doubling the engine effeciency of the internal combustion engine from the mid 20% range to about 41%.

I'm extremely skeptical of that. Firstly, Diesels don't come anywhere near that kind of efficiency despite 20:1 compression ratios and higher as well as denser fuel. And, to top it off, Diesels don't have the added pumping loss associated with pumping against a closed-throttle. (Since diesels have no throttle.)

Now, IIRC, E95 is supposed to be a diesel replacement. That might prove to be more fuel-efficient.

-Adrian
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Old 09-15-2005, 09:00 AM   #95
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Quote:
Originally Posted by SaabTuner
I'm extremely skeptical of that. Firstly, Diesels don't come anywhere near that kind of efficiency despite 20:1 compression ratios and higher as well as denser fuel. And, to top it off, Diesels don't have the added pumping loss associated with pumping against a closed-throttle. (Since diesels have no throttle.)

Now, IIRC, E95 is supposed to be a diesel replacement. That might prove to be more fuel-efficient.

-Adrian
your have to look at all kinds of things...caloric value, desnity, burn rates, etc...
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Old 09-15-2005, 10:18 AM   #96
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Quote:
I'm extremely skeptical of that. Firstly, Diesels don't come anywhere near that kind of efficiency despite 20:1 compression ratios and higher as well as denser fuel. And, to top it off, Diesels don't have the added pumping loss associated with pumping against a closed-throttle. (Since diesels have no throttle.)

http://www.epa.gov/otaq/presentation...02-01-2743.pdf


Quote:
no, nascar doesn't run E85...
Yet !!

Larry
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Old 09-15-2005, 12:08 PM   #97
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Well, still no definite answer to my question, but I think I'm going to try some in my '05 STI since it is available in AZ. I'm thinking it can't hurt because we get a 10% ethanol blend during the winter months anyway here.

My car has been pinging like crazy during the hot summer months here, and from what I have read so far a small amount of E85 might help that.

hmmm...
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Old 09-15-2005, 05:22 PM   #98
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do it...
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Old 09-15-2005, 07:58 PM   #99
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Larry,

I will first admit that I need to go back and read more on E85 but I did skim this thread and it's very interesting. In my VW Golf 2.0L 2000 model, I decided to try a 30/70 mix. When it ran a tank of that fine I increased the mix to an exact 50/50. Still runs fine, no CEL. What's the possible problems that may arise if I push the E85 mix further, say a 75/25? I can tell a definite increase in available power, especially since it's a low output engine in the first place I figured the 50/50 mix to be about 96 octane.
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Old 09-15-2005, 10:27 PM   #100
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I think the VW was one of the cars used in alcohol fuel testing in Brazil so there is a remote possibility it has an undocumented ability to handle the fuel.

I understand that the Bosch fuel pumps are alcohol safe.

It depends a bit on how your engine management works. On OBDII systems when you run out of fuel trim you will get a CEL. My understanding is it should be safe at least that far. If for some reason you don't see a CEL and the system cannot adapt to the new fuel you will gradually lean out the mixture as you add E85. Due to the high octane of the fuel, it is less detonation prone at lean mixtures than for gasoline, but really lean mixtures on alcohol are just as dangerous as really lean mixtures on gasoline.

Id get a check on your mixture if you push really high E85 blends with no modifications. If the car has adequate fuel trim authority, you could probably run 100% E85 with no problems but I would be surprised if you car has enough fuel trim authority to add 27% mixture. It could but I would be inclined to check as you get to the higher blends if you can find a wideband O2 sensor, just check your mixture using the Lambda function to get true mixture readings.

There would also be some possible minor fuel compatability issues to rubber fuel hose, o rings etc. But my understanding is that most modern cars no longer have issues with that. If you have a plastic gas tank some of them do not like alcohol in high blends.

As always when doing these sort of experiments its a "buyer beware" Proceed at your own risk situation. Welcome to the "fuel ethanol lab rat society"

Larry
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