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rbodor3

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Ahhh, so it the chart that 550 posted incorrect? It's what I based mine off of.

Here in AZ 91 is premium. So there'd still be a gain ... however if E85 = 94 then it would take 33% E85 just to raise ONE full octane point. That's fairly disappointing then. Even a full E85 conversion hardly seems worth it compared to adding some race gas to premium. And with the greater quantities of E85 needed vs Gas I can't see the value in swapping.

Thats wrong also. Another thing to remember this is all based on 55 gallon drums. Crap in the inground tanks is garbage compare to race grade E85. Just use MTBE like a normal person. Or low terta lead.

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Ahhh, so it the chart that 550 posted incorrect? It's what I based mine off of.

Here in AZ 91 is premium. So there'd still be a gain ... however if E85 = 94 then it would take 33% E85 just to raise ONE full octane point. That's fairly disappointing then. Even a full E85 conversion hardly seems worth it compared to adding some race gas to premium. And with the greater quantities of E85 needed vs Gas I can't see the value in swapping.

I wouldn't say it's wrong, I think you are misinterpreting the octane with the stoichiometric properties. Just because the octane rating of E85 isn't necessarily 105 doesn't change where E85 is stoichiometric.

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I wouldn't say it's wrong, I think you are misinterpreting the octane with the stoichiometric properties. Just because the octane rating of E85 isn't necessarily 105 doesn't change where E85 is stoichiometric.

Not its craptastic octane rating its craptastic hydrophilic properties.

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Ahhh, making more sense to me now. Is the additive to premium gains just a butt dyno feeling then? assuming both are simply gas station sludge that is.

I could see it being a more feasible setup if one were to buy the drums directly (I know sunoco lets you). Then create whatever mixture you want.

Still, seems hardly worth it compared to some race gas or other additives available as Chuck suggests. At least for a street car anyways.

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I've been using the Lucas Motorsports octane booster for years now. I remember reading your article a while back and confirming what my butt dyno already knew. I am still curious to see what guys try doing with E85 on our volvos though. See if there's any definitive evidence to support it as a worthwhile octane booster. I'll stick with Lucas or a splash or race gas for now though.

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While the octane rating thing is controversial, it is not controversial that E85 is a knock suppressant and allows for more boost or ignition timing, while also cooling the intake charge upon injection.

Here's a good paper: http://www.ethanolboost.com/LFEE-2006-01.pdf

Our Formula SAE team runs E85 on a 12:1 compression sport bike engine running 8psi and no intercooler, and our engine failure mode is blowing up transmissions from the extra torque, not detonation. Just make sure your fuel system is compatible, which isn't really that hard. E85 and rubber don't get along, and if you use aluminum it should be anodized. Fuel lines with teflon liners work perfectly.

With all the new direct injection engines coming out (ecoboost 4 cylinders in the new volvos), E85 gives an even greater performance advantage due to better use of it's latent heat of vaporization. Look up what the chevy cobalt guys are doing with 54mm turbos (500+whp).

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E85 and octane are both worthless unless the vehicle is tuned to use it, or designed to in some cases. Thats the big joke about octane boosters. In a NA engine adding octane is really only going to get you back to stock levels with no timing pull. To go beyond a few % over stock you have to change things like compression or rpm to take advantage of it. E85 is an ok fuel for racing but makes almost zero sense in a street car unless you can buy it subsidized.

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True, but if you have a boosted street car that you can easily retune it is a lot cheaper than say, C16, and worth a substantial fraction of the performance. On the lowest level, you just scale your fuel maps for the new stoich ratio and you get all the cooling benefit without any real tuning, and spark retard from the knock sensor will be a thing of the past. Then if you feel like it you can turn up the boost or whatever to get all the benefits.

I've seen some people incorporate the GM flexfuel sensors into their engine management so that they can fill up with gasoline and putt around, then put E85 in and get all the performance back without doing anything, and you have a very failsafe system on top of it if the E85 is actually E50 or something.

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I've got some E85 maps done... the timing curves are awesome and so is the power but I've done very little testing long term so I can only weigh in as it regards power development.

To be honest I just put Greens in a car and adjusted the VE slightly since they are already 24% larger than stock and get you pretty close to the 30% increase in fuel that E85 needs relative to gasoline. It's a touch more complex than that but not hugely so.

I'm happy to provide a tune to Volvospeed for trial, maybe something VS can do as a proper test thread??? Chuck that's your cue...

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I've got some E85 maps done... the timing curves are awesome and so is the power but I've done very little testing long term so I can only weigh in as it regards power development.

To be honest I just put Greens in a car and adjusted the VE slightly since they are already 24% larger than stock and get you pretty close to the 30% increase in fuel that E85 needs relative to gasoline. It's a touch more complex than that but not hugely so.

I'm happy to provide a tune to Volvospeed for trial, maybe something VS can do as a proper test thread??? Chuck that's your cue...

Hands down the best person would be monkeyboy.... Beinglax. Hes bias but hes had a hard on about this for a long time. If he would be willing to do some dyno pulls he would be perfect person to try it out.

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