Anyone using E85

[clay69camaro]

Nice, Are there still benefits to running E85 on a naturally aspirated build?

[Flash68]

Originally Posted by clay69camaro

Nice, Are there still benefits to running E85 on a naturally aspirated build?

Absolutely. It's really 2 parts of analysis in my mind... one is the octane benefit (105 vs 91 for us in Calif). But then it does consume more fuel apples to apples compared to pump gas, but I don't know about you... I would not care if my MPG went from the current 10 down to 7 or 8. I'll take the ability to tune for more power based on the 105 octane rating.

[skatinjay27]

isn't that 105 rating not a minimum like regular fuels numbers are?

[clay69camaro]

Good point Flash, Thanks for your input.

Don't know what part of Norcal you are in but there are a lot more E85 stations up there than down here. I'm in Orange County, and there are no stations close by

[Flash68]

Originally Posted by skatinjay27

isn't that 105 rating not a minimum like regular fuels numbers are?

From my research you definitely have to be careful of what exactly you are buying and where you are buying the E85. It can vary but 105 octane is attainable from what I've read -- like anything, buyer beware, and you have to do your research. I've seen you can get as low as 95-96 octane and as high as 105. You can also buy in drums if you'd like, which is what my buddy back in South Dakota does with his converted race car. He pays like $2/gallon and gained 3 tenths in his 10 second drag car - no other changes.

[wmhjr]

105 octane is a very common myth for E85. E85/Ethanol is not 105 Octane. it is actually using 93-95 octane. Any quotes of 105 octane are based on an "interpretive" method of labeling octane based on the blending ratio of E85 - and NOT an actual octane measurement. It behaves differently, allowing a cooler fuel burn which sometimes results in similar effects such as you would get with high octane gasoline, but it is not 105 octane. If you're running wideband, it also requires a far far richer A/F ratio than gasoline. Almost 50% richer. General guidelines for gasoline are around 14:1. E85 is around 9:1.

By itself running E85 does not make more power. It actually makes less. You can sometimes however increase compression, etc with ethanol/alcohol to make more power. Typically that involves boost.

A recent engine builder shootout using E85 to build the highest power output naturally aspirated engines resulted in those engines producing less power than similar gas engines.

[TurboNova]

That is funny and exactly opposite to what we have found here on the dyno. On one test we switched from C12 to E85 from the station across the street and found 25hp with no changes to the timing. I love the stuff because the jetting is more stable, when you find peak power and add more fuel it usually does not drop in power for several jet sizes then if you set the engine up to run at the middle of the jet spread it will not be effected by outside temp as gas is.

For me there is no down side for E85, it is a no brainer. You did touch on A/F for E85 and gas but are off on the numbers a little.

Air/Fuel Ratio Gasoline E85
Stoichiometric 14.7:1 9.7:1
Max power 12.5:1 6.9:1
Max poower 13.2:1 8.4:1

Most A/F gages also read in Lambda and that is the scale you should be using either anything other than Gas.

[wmhjr]

For the A/F, those were just general off the cuff numbers. All A/F wideband are Lambda - often presented as something else but the measurements are always Lambda to start with. Keep in mind that for example, 14.7:1 will not necessarily yield the most power for a gas engine. Those again are generalizations - which is why I stated "around" certain numbers.

I would encourage anyone interested to really read up rather than depending on one or two peoples "personal stories". In my experience and until I see differently, for non-boosted motors, E85 is not a solution. If somebody picked up power by doing nothing but switching to E85, they had a poorly setup motor to start with.

In build-off contests including those specifically targeted at ethanol and E85 engines, there has yet to be a single engine built (non-boosted) that equals a similar displacement gas engine build of similar design and "category".

E85/Ethanol/Alcohol do provide definite benefits for boosted applications.

As you might have realized, I am a very big critic of Ethanol. I find very little positive to say about it. Yes, it has some advantages, but they are massively outweighed by all the down sides- IMHO. And that doesn't even get into the fact that it's a total loser from a practical sense - AND that it can really cause issues. Ever wonder why marine fuel does not contain ethanol?

[RSZ28]

Originally Posted by wmhjr

105 octane is a very common myth for E85. E85/Ethanol is not 105 Octane. it is actually using 93-95 octane. Any quotes of 105 octane are based on an "interpretive" method of labeling octane based on the blending ratio of E85 - and NOT an actual octane measurement. It behaves differently, allowing a cooler fuel burn which sometimes results in similar effects such as you would get with high octane gasoline, but it is not 105 octane. If you're running wideband, it also requires a far far richer A/F ratio than gasoline. Almost 50% richer. General guidelines for gasoline are around 14:1. E85 is around 9:1.

By itself running E85 does not make more power. It actually makes less. You can sometimes however increase compression, etc with ethanol/alcohol to make more power. Typically that involves boost.

A recent engine builder shootout using E85 to build the highest power output naturally aspirated engines resulted in those engines producing less power than similar gas engines.

With you on 50% more fuel flow which makes it hardly worth it unless it is 2/3 the price of hi octane. But it is a lot more knock resistant than the highest rated gas I can get (95).

Been running it for almost 3 years in a 68 Camaro with LS7. Ricks tank but regular fuel lines even with bare steel in them and no issues.

More power? There is no traction below 4th gear so hard to measure .

It is very clean, cleaner than gas by most measurements, but is way over on formaldehyde.

[Croaker]

If you're running a boosted application and you're already fuel injected, you can always set up the system with a fuel composition sensor and just dial the boost back when you don't have access to E85. I know White Racing and Marine has the ability to set up FAST, BS3 and Accel to work with flex fuel. I'm sure they're not the only ones around with the capability.