blown engine on e-85 600 miles......
#33
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don't you know what stoich is on ethanol (e-85) varies batch to batch but is in the low nines/high eights...
Last edited by homemade wrx; Jul 19, 2007 at 12:24 PM.
#34
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why doesn't anyone use lambda?
nearly every wideband displays lambda, and with lambda you don't have to calibrate for different fuels. .8 on gas is also .8 on E85.
i think many people miss the point on how he can say his wideband was reading 11.5AFR on a gas calibrated wideband, and how that is equivalent to .78 lambda, or an AFR of 7.6 when using E-85. so he was not running 11.5 AFR on E-85, if he was, thats why his engine blew.
nearly every wideband displays lambda, and with lambda you don't have to calibrate for different fuels. .8 on gas is also .8 on E85.
i think many people miss the point on how he can say his wideband was reading 11.5AFR on a gas calibrated wideband, and how that is equivalent to .78 lambda, or an AFR of 7.6 when using E-85. so he was not running 11.5 AFR on E-85, if he was, thats why his engine blew.
#36
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why doesn't anyone use lambda?
nearly every wideband displays lambda, and with lambda you don't have to calibrate for different fuels. .8 on gas is also .8 on E85.
i think many people miss the point on how he can say his wideband was reading 11.5AFR on a gas calibrated wideband, and how that is equivalent to .78 lambda, or an AFR of 7.6 when using E-85. so he was not running 11.5 AFR on E-85, if he was, thats why his engine blew.
nearly every wideband displays lambda, and with lambda you don't have to calibrate for different fuels. .8 on gas is also .8 on E85.
i think many people miss the point on how he can say his wideband was reading 11.5AFR on a gas calibrated wideband, and how that is equivalent to .78 lambda, or an AFR of 7.6 when using E-85. so he was not running 11.5 AFR on E-85, if he was, thats why his engine blew.
#37
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did you guys recalibrate yours out at UTA I know I did at ODU...just for the dummies on the team though...used mass on the dyno.
yeah, definately didn't do it...need to make a habit of seeing how old threads are before posting
#38
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Something is wrong with your wideband or boost gauge or something, because 780CC injectors cannot support a maxed out 20G using E-85.
780cc*4=3120cc/min
E-85 sg .78
3120*.78=2433.6g/min = 5.36 lb/min E-85
E-85 stoich is about 9.7:1 AFR, or 1.0 lambda = same as 14.7 AFR on your gas wideband
Using your gas wideband, your injectors could support the following air flow:
11:1 (.75 lambda, which is .75*9.7=7.3 AFR E-85) - 7.3*5.36lb/min E-85 = 39 lb/min airflow
12:1 (.82 lambda) - 42.6 lb/min airflow
13:1 (.88 lambda) - 46 lb/min airflow
14:1 (.95 lambda) - 49.5 lb/min airflow
So, if you are maxing out your 20G, which I would assume you are, holding 28-29 psi with 280 cams, etc, then your 780CC injectors are nowhere close to 11.5:1 as you say. The math shows that you were running more like 14:1 AFR. This is of course assuming that you are maxing out your 20G, which would flow close to 50 lb/min.
Also, one other factor may be the fact that any water comtamination in your oil/E-85 can cause formic acid to form, which could easily contribute to a spun bearing, I would presume.
Eric
780cc*4=3120cc/min
E-85 sg .78
3120*.78=2433.6g/min = 5.36 lb/min E-85
E-85 stoich is about 9.7:1 AFR, or 1.0 lambda = same as 14.7 AFR on your gas wideband
Using your gas wideband, your injectors could support the following air flow:
11:1 (.75 lambda, which is .75*9.7=7.3 AFR E-85) - 7.3*5.36lb/min E-85 = 39 lb/min airflow
12:1 (.82 lambda) - 42.6 lb/min airflow
13:1 (.88 lambda) - 46 lb/min airflow
14:1 (.95 lambda) - 49.5 lb/min airflow
So, if you are maxing out your 20G, which I would assume you are, holding 28-29 psi with 280 cams, etc, then your 780CC injectors are nowhere close to 11.5:1 as you say. The math shows that you were running more like 14:1 AFR. This is of course assuming that you are maxing out your 20G, which would flow close to 50 lb/min.
Also, one other factor may be the fact that any water comtamination in your oil/E-85 can cause formic acid to form, which could easily contribute to a spun bearing, I would presume.
Eric
#39
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Why is this formic acid not a problem when injecting straight water, or a water/alky mix, through a regular alky injection kit into the upper IC pipe or manifold?
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How long did you have the car on e85 before the enging blowing? I see you put 600 miles on it, but e85 draws moisture from the air. If your oil was contaminated with E85, it will pull water into the oil as well. Valvoline VR1 conventional oil is designed to work with alcohol based fuels as well as some of the racing only synthetics (redline, ams, shaffers, ect). You have to confirm it's compatable either from there web site or directly from the manafacture. I wouldn't trust a dealer because the majority of them just want to move the product off there shelf. Anyone running E85 should be changing there oil and filter at least once a month, or every 2 track events with a compatable oil. If your daily driving on it you should be inspecting the oil on your dipstick at least twice a week. Nobody ever said going fast would be easy or cheap. If they did I want a hit of what there smoking.
#41
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I used valvoline vr1 20w50 and prolly changed my oil once a week because of this exact problem, I now know what the problem was, It was way rich and had close to stock timing. I totally blame the tuner whose name I won't mention because they have way too many nutswingers for them to have ever made a tuning mistake. I have tuned my friends evo on e-85 and it hauls *** with very aggressive timing thrown at it and no knock. He has 780cc and a pump. Timing is definitely where the power is made on e-85. I have since blown a fully built motor with the same rod bearing problem so I gave up on the evo and went 2jz power. I will play with e-85 again just not on my car.
#44
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http://forums.nasioc.com/forums/showthread.php?t=803341
Originally Posted by hotrod from NASIOC
Here are some comparisions of stoichmetric fuel mixtures for different fuel blends:
======== stoichmetric AFR ===== max power rich AFR
Gasoline ---------- 14.7:1 -------------------12.5
100% E-85 ------- 9.73-9.8:1 ------------- ~ 9:1 - 8:1
100% fuel ethanol - 9:1 ------------------- ~ 7.2:1
======== stoichmetric AFR ===== max power rich AFR
Gasoline ---------- 14.7:1 -------------------12.5
100% E-85 ------- 9.73-9.8:1 ------------- ~ 9:1 - 8:1
100% fuel ethanol - 9:1 ------------------- ~ 7.2:1
#45
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Well I am sure it has been covered in this thread if he was using Gas readings not ALC the 11.5 is a good spot on a gas WB. From my E85 testing with over 50+ mid 11sec passes on it and close to 10k in mi I have found 11.5 on a gas WB is safe and my car runs low 12s out the top due to being out of fuel on my 850's. My car has a stock motor and has been spiking 31psi holding 24psi to redline the hole time and knock on wood has been great. Even has stock head bolts.
If you type in rod bearing on here you will find a min of 1 post per month on a spun bearings. These are the same crank and rods that have been in 93+DSM for years and they also have rod bearing problems.
So maybe the bearing was on its way out from being beat on a a bad pump tune or what ever random problem that the motor could have and making the extra power from the E85 tune just finished it off.
Unless you have a 2nd pump and are running a high base I cant see 750s even coming close on a Evo Green.
I have been running normal syn oil the whole time. Yes it does smell like E85 very fast but does not get milky or seem to be breaking down. Really is hard to find any good info on Ethanol on the net. 99.9% of all the info you find on ALC is Meth which from what I can tell is noting like Ethanol.
If you type in rod bearing on here you will find a min of 1 post per month on a spun bearings. These are the same crank and rods that have been in 93+DSM for years and they also have rod bearing problems.
So maybe the bearing was on its way out from being beat on a a bad pump tune or what ever random problem that the motor could have and making the extra power from the E85 tune just finished it off.
Unless you have a 2nd pump and are running a high base I cant see 750s even coming close on a Evo Green.
I have been running normal syn oil the whole time. Yes it does smell like E85 very fast but does not get milky or seem to be breaking down. Really is hard to find any good info on Ethanol on the net. 99.9% of all the info you find on ALC is Meth which from what I can tell is noting like Ethanol.
No, that's quite LEAN for E-85. Rich for E-85 is 8-9:1.
http://forums.nasioc.com/forums/showthread.php?t=803341
-Adrian
http://forums.nasioc.com/forums/showthread.php?t=803341
-Adrian