:::RHMT::: Real Home Made Turbo
General Category => Engine Management => Topic started by: chris on May 31, 2010, 05:58:10 AM
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Anyone have any hands on with the power gains with running e85? From a buddy of mine who just tuned his s2000 on it is that the motors want alot of timing with it.
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It wants timing if you run it lean. Run it rich and it likes gasoline-like timing.
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guess no one runs e85 on here. WEll looks like Ill be the test dummy.
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No, people run it. You didn't ask any questions about it.
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ass dyno felt good
haha
it felt like my mid range tq was nuts after i switched
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I made 620hp on e85 at 21 psi did not compare the pump gas power at the same boost, but I made 440whp on pump gas at 15 psi.
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guess no one runs e85 on here. WEll looks like Ill be the test dummy.
What do you want to know??
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Anyone have any hands on with the power gains with running e85? From a buddy of mine who just tuned his s2000 on it is that the motors want alot of timing with it.
Are you asking will X engine make more power on e85 at the same boost as pump gas? In theory, it should. The real world with the required tuning compensation for fuel/timing, along with whatever combination of engine parts might not make the same power. Just depends on the setup.
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I asked TOny Palo a while back, he said the average for all things equal is ~8%. But since you can run more timing, boost, heat, etc - it ends up being more when you max ethanol and gasoline out on the same setup.
Still 20-30hp for just using a different gas pump is pretty cool.
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But since you can run more timing,
Required timing is a property of the fuel, and that a non iso-octane based fuel requires more timing is neither an advantage nor a detriment, merely an inherent property of that fuel. As such, everybody needs to stop lumping it in with all these lists of benefits of E85, because it has nothing to do with anything like that.
OK
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I don't have any masters or phd's in anything automotive-related, hell I didn't even finish the 4th grade, but I can tell you putting peak cylinder pressure at a certain crank angle to give the greatest average cylinder pressure will make the most power. Not many 'vanilla' pump fuels allow you to put in the timing that allows that. Ethanol may make more power because it's oxygenated, but it also makes power because it indeed supresses knock.
If a fuel allows you to get closer to this theoretical perfect timing vs other widely-availible gasoline, I'd consider it a benifit. We don't all live in hicksville where the corner pump is leaded.
JDSAP
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I don't have any masters or phd's in anything automotive-related, hell I didn't even finish the 4th grade, but I can tell you putting peak cylinder pressure at a certain crank angle to give the greatest average cylinder pressure will make the most power. Not many 'vanilla' pump fuels allow you to put in the timing that allows that. Ethanol may make more power because it's oxygenated, but it also makes power because it indeed supresses knock.
If a fuel allows you to get closer to this theoretical perfect timing vs other widely-availible gasoline, I'd consider it a benifit. We don't all live in hicksville where the corner pump is leaded.
Domestic V8s operate like that unless you specifically rework them not to, which may or may not be money well spent. 99% of inline 4's do not, and the ones that do are like that because you did something wrong.
With an inline 4 you will make peak power with an optimally placed pressure peak 3-5 degrees before the motor will start to detonate.
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Well my LS at 20 psi on pump, & Leed tuning it and it didnt give a fuck about timing. With a bunch in, and a bunch pulled it made damn near the same power. Now this is 1 setup out of bunch. But more timing dose not always = more power. Like JD said, "LS make gobs of tq and could car less about timing."
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LS are an exception to the rule. They are an exception to every rule, actually. Nothing else forced induction cares so little about timing.
AJ, step up the cams in your motor. 402T are best if you have a poorer flowing manifold like a casting, otherwise 403/404 depending on how free flowing.
I really like the idea of the 272s, I think there is something there but it's a play with cam gears proposition. After you buy that dyno time you could have bought some cams and made gobs more power without worrying about it.
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i rain it in my car still do right now, but NA
last setup was 8.5 wisecos on a 62-1 h22 21 psi made 525/404 on a dynodynamics but shane from DB left it rich because there can be quite a bit of variance in e85 quality especially in my climate. and the fact that leaning it way out wouldnt yield enough of a gain to care.
and right now im running pump timing on an okay make pretty lean at idle (too lean) and a okay the rest of the map, on my 12:1 cr hybrid f23/h22. no idea on the power...
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but when i use it im looking at the 106ish octane, and to use it just for high boost apps or high compression apps. i would rather use pump gas if i didnt use lots of boost or high compression. pump because i would rather get more than 200 miles to the tank(10 gals). i get about 23 avg highway.
but i guessit might average out idk.
e85 1.91-2.10 a gallon
pump 91 octane 2.75+ a gallon
and im in iowa
chris what kinda of setup are you wanting to try?
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English, motherfucker.
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English, motherfucker.
E85 squirt boom go. Refuel often.
What I was trying to get across is that with E85, it technically will increase that 3-5 degree gap between peak power and detonation. That allows for a safer tune, since any little detrimental change over time would keep you that much further from detonation. Maybe so much so that it will stop B16 sleeves from peeling like bananers much to JD's dismay.
One thing I found is that the tetra-ethyl lead guys were looking to slow down the burn speed, and most people agree E85 burns a little slower. AFAIK, that would reduce peak cyl pressure but increase avg cyl pressure.
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English, motherfucker.
reduce peak cyl pressure but increase avg cyl pressure.
If this is true... fap fap fap.
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Yeah, but E85 is an unregulated witches brew whose exact properties change almost tank to tank. What timing it likes is huge compared to gas, and is slaved to AFR. When that AFR changes tank to tank, what of timing?
Until our standalones can account for this with an ethanol sensor like GM/others run, keep your eye on that shit.
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Yeah, but E85 is an unregulated witches brew whose exact properties change almost tank to tank. What timing it likes is huge compared to gas, and is slaved to AFR. When that AFR changes tank to tank, what of timing?
Until our standalones can account for this with an ethanol sensor like GM/others run, keep your eye on that shit.
So then test and mix your own so its always the same. Plenty of people do that.
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Make ethanol. Hydrometer that shit. Profit.
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Yeah, but E85 is an unregulated witches brew whose exact properties change almost tank to tank. What timing it likes is huge compared to gas, and is slaved to AFR. When that AFR changes tank to tank, what of timing?
Until our standalones can account for this with an ethanol sensor like GM/others run, keep your eye on that shit.
So then test and mix your own so its always the same. Plenty of people do that.
That's a lot of fucking around.
Make ethanol. Drink that shit. Profit.
Fixed.
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Yeah, but E85 is an unregulated witches brew whose exact properties change almost tank to tank. What timing it likes is huge compared to gas, and is slaved to AFR. When that AFR changes tank to tank, what of timing?
Until our standalones can account for this with an ethanol sensor like GM/others run, keep your eye on that shit.
There is some table that shows what % is supposed to be run at various times by state. I really doubt you'll be on the bleeding edge of timing where the motor can't withstand a 5% change in ethanol. Hell there can be more variation at a normal gas pump due to the stickers saying "UP TO 10% ethanol". Some places use 0%, some >10%. Considering E85 isn't at every pump, most e85 users will refill at the same station. E10 users will end up with worse consistency since they'll blissfully use any old gas station.
Anyways, I've seen some Subie guy make a meter with a GM sensor and his own electronics to show the sensor output as a %, but there seems to be a cheaper and just as reliable method (most scan tools consider the data bad). You add some water & fuel to a cylinder, shake it, take a massive BDVT shit, and check the results:
http://forums.evolutionm.net/alternative-fuel/397007-poor-mans-ethanol-content-analyzer.html (http://forums.evolutionm.net/alternative-fuel/397007-poor-mans-ethanol-content-analyzer.html)
http://www.fuel-testers.com/product_gas_alcohol.html (http://www.fuel-testers.com/product_gas_alcohol.html)
I don't give 2 shits about people with static tunes, since I'll always be able to plug in and adjust afr's at the pump. I'll also be able to deal with changes since I actually have my o2 sensor making corrections while I cruise home.
So then test and mix your own so its always the same. Plenty of people do that.
That's a lot of fucking around.
You can't tell me a perfectionist like yourself hasn't spent a good portion of your day on things that show smaller gains. Remember this is a site for broke-ass naggers that use light fixture chains for wastegate actuators, not ballers that buy VP C16 by the barrel.
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The table that show the ethanol % only state a minimium amount of ethanol specified.
Ethanal does have a faster burn rate than gas. Heres the kicker about e85, the more gas it has in it the more timing you need to run. I had a bunch of local cars that when they switched to the winter blend(more gas, less ethanol) had to be retuned, they all took about 5 degrees more timing to make the same power as they did before. I have dyno sheets and corresponding track slips to back that statement up.
I do agree a small swing in ethanol % doesnt make much of a difference, but that isnt typically the case. I've seen a afr swing from tank to tank of e85 be as high as 3 pts. I've seen e85 have 98% ethanol, and i've seen it have 74%.
The e10 users are fine, because the % of change is fairly small, and you need roughly 30% more fuel for ethanol so that 10% swing, really is smaller than that. Typically gas stations run the max ethanol allowed, its cheaper than gas so the more ethanol they use the more money they make.
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Peniswhistle.
I like E10 "gasoline" - in fact I wish 93 octane was E10. If they could regulate it at a true E10 for me I'd be super happy.
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Peniswhistle.
Spudnigger.
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Peniswhistle.
Spudnigger.
Mudcricket
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Peniswhistle.
Spudnigger.
Mudcricket
Only one of these is the next, true EMS.
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A quick search finds me a megasquirt page that allows adjustments based on a flex-fuel sensor. Mainly for AFR's iirc, but it's a start.
Sewell thanks for that info. It sucks there's so much variability. Unfortunately since flex fuel cars adjust automaticly, nobody cares. Not until we see engines designed for ethanol-only. However that brings me back to a post I made in the fab forum - 16timer... 16 tunes on one chip. Not exactly viable for someone paying $600 per tune, but viable for diy'ers.
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A quick search finds me a megasquirt page that allows adjustments based on a flex-fuel sensor. Mainly for AFR's iirc, but it's a start.
Sewell thanks for that info. It sucks there's so much variability. Unfortunately since flex fuel cars adjust automaticly, nobody cares. Not until we see engines designed for ethanol-only. However that brings me back to a post I made in the fab forum - 16timer... 16 tunes on one chip. Not exactly viable for someone paying $600 per tune, but viable for diy'ers.
NP. I'm just trying to spread info i've learned and seen first hand.
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most good standalones have been letting people use the GM flex fuel sensors for a long time. Lots of overpaid princesses on bf.c using them with DTA/MS/AEM/varied euro noggery.
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most good standalones have been letting people use the GM flex fuel sensors for a long time. Lots of overpaid princesses on bf.c using them with DTA/MS/AEM/varied euro noggery.
Stop trying to use our words to fit in. :(
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most good standalones have been letting people use the GM flex fuel sensors for a long time. Lots of overpaid princesses on bf.c using them with DTA/MS/AEM/varied euro noggery.
Stop trying to use our words to fit in. :(
fuck you Denice the Menace!!!!!!
Chuck
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most good standalones have been letting people use the GM flex fuel sensors for a long time. Lots of overpaid princesses on bf.c using them with DTA/MS/AEM/varied euro noggery.
Stop trying to use our words to fit in. :(
fuck you Denice the Menace!!!!!!
Chuck
Suck my nutz Charlene
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Chucklene.
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But since you can run more timing,
Required timing is a property of the fuel, and that a non iso-octane based fuel requires more timing is neither an advantage nor a detriment, merely an inherent property of that fuel. As such, everybody needs to stop lumping it in with all these lists of benefits of E85, because it has nothing to do with anything like that.
OK
So you're saying you can run more timing? :P