Considering an E85 Experiment

[redpoint5]

Originally Posted by Allch Chcar

Ethanol is infact heavier than Gasoline. Being 33% oxygen makes it heavier and reduces it's energy density. It's also what makes it so energy efficient.

If I understand what you are saying, Ethanol is more weight dense than gasoline but less energy dense? How does oxygen make it "so energy efficient" and compared to what?

Since oxygen is floating all around, it seems lugging it about in a fuel tank is a waste of space and weight.

[serialk11r]

It cools the charge, increasing knock resistance, increases max torque, and improves thermodynamic efficiency in several ways. Despite the energy per unit oxygen burned is about the same, people who run E85 see increases in power, and it's also why some vehicles get the same fuel economy (in gallons of fuel consumed) on E85 despite E85 having less fuel energy per unit volume.

[Allch Chcar]

Originally Posted by redpoint5

If I understand what you are saying, Ethanol is more weight dense than gasoline but less energy dense? How does oxygen make it "so energy efficient" and compared to what?

Since oxygen is floating all around, it seems lugging it about in a fuel tank is a waste of space and weight.

Yup, counter-intuitive isn't it? Oxygen is what makes the alcohols more energy efficient though. Granted there are engines that get MPG based on energy content, I've seen studies to verify this but then there are cars that people are getting much less to almost no loss that haven't been tested or aren't even FFVs!

Another thing to remember is that while E10 has 97% of the energy content of "pure"(I use that to mean no Ethanol) Gasoline. E85 has 71%, E70 has 76% of the energy content. By my calculations. The difference between E10 and E70 is 22% less energy. That doesn't explain the 15%-5% loss some people are getting but people forget the blends change or don't have a test kit. It's not as impressive if people are seeing a 15% loss on E70. But it's still an improvement :/

[ZR1-S10]

Well my tank of E14 is now gone and I have the results. No drop in mileage!

22.3 MPG on E10 with my normal routine
22.3 MPG on E14 with a few long hard WOT runs for testing purposes

Also no check engine light, hards starts, rough driving or any other side-effects so now I've filled up with E21 and will give that blend a try.

[ZR1-S10]

I'm loving this! This mileage is ALL CITY.

22.3 with E10
22.3 with E14
22.6 with E21 A new best for me!


Still no check engine light or other side-effects.
So now I just filled up with E26.

[ZR1-S10]

WOW with E26 my mileage JUMPED UP to 23.8 this is with me driving 5 MPH FASTER as well as some WOT runs.

I'm happy with this Ethanol incresse for my truck. I'm NEVER going back down to E10 again. It's now just time to get the mix "just right".

[Allch Chcar]

Interesting,keeping the same MPG is fascinating enough please continue to record your findings.

[roosterk0031]

How are getting those numbers?

Using a scangage in my car it needs recalibrated every blend so it's numbers are no good, had to go tank to tank.

[Allch Chcar]

Originally Posted by roosterk0031

How are getting those numbers?

Using a scangage in my car it needs recalibrated every blend so it's numbers are no good, had to go tank to tank.

What do you recalibrate?

[Lessendz]

Ethanol is a weak choice as a fuel for internal combustion engines..
it does a good job fueling drunk people at bars tho??

Expensive to create competitively in Neat form..
essentially it becomes like a mime when mixed with Gasoline up to 10%
E10 has many combustion characteristics very similar to Neat Gasoline,
Vapor form Characteristics tend to be slightly different tho..

Stronger blends will pull more alcohol Characteristics.
which can be both a good & bad thing!
its a weak alcohol to use because you end up blending in a large% of alcohol to get small gains in alcohol characteristics you'd like in a *fuel*
unfortunately that same Larger % of ethanol will attack the fuel storage/delivery system even quicker than E10 does..

for the guy with the Turbo Evo wanting to run E85
you should worry more about your fuel lines turning to mush and clogging your fuel filter,
opposed to whether you have enough injector or if yer ignition timing is too advanced..
in general ethanol turns rubber fuel lines soft & sludgy..
Methanol will dry out & crack the rubber(like aromatic components of gasoline)
The alcohol guyz usually switch out to PTFE type lines (teflon/steelbraided is the usual choice)
u can also use Flourine enhanced rubber lines but they are SUPER expensive like $20/foot
and don't like Cold tempatures..
also oil changes are needed Much more frequently with E85
(alcohol use tends to turn the oil watery instead of dirty and dark)

i personally think you may be able to get away with slightly stronger blends with Ethanol
i'm assuming your engine was tuned on E10 close to MBT w/some cushion
Using a slightly higher% blend, MBT ignition timing may no longer be knock limited as it was on E10.. mostly due to the blended fuel's New chemical composition of more "alcohol"

but since you're Living in L.A.
you should analyze what your Goals are?
whether its MPG's, 20Psi boost / Power, or regulated Emissions
if you're just wanting to play Dr.Jekyll / Mr.Hyde with the car on weekends..
i'd suggest small% Meth blends into E10 pumpCrap
& just read the plugs real quick to check your ECU Tune's High blend tolerance.

BTW: i'm willing to bet a M20 style fuel destroys E85 on the Dyno & on the street..
i specifically had my stock internal SR20DET tuned on a M20 blend
we Spool'd a GT35R by 4800rpm on a DynoJet248
400lb/ft Torque
the Full-race website has dyno charts of GT30's that need their hyped up divided manifolds to spool that Quickly!!
(we used their old undivided type)