[charlie66]

So i went up to the BP station where the E85 was 95% 2 weeks ago and 90% last week and tested it today . It was 84% now..

[Scott65]

Should be getting closer to 70 real soon.

[charlie66]

Probably will be.

Im going to do a week by week test over the winter in my gas tank to see its decay rate.

[Sirrotica]

They start making seasonal changes in fuel about mid October. This is diesel, gasoline, and of course E 85. The batches change as of whatever date the racks switch over the blends of the tankers, but it depends upon how much fuel the station sells how fast summer blends get diluted with winter fuel.

A high volume station the blend change will come about very quickly. Low volume of course takes longer. Since most operators need to run the volume down so they can store 7800 gallons in their tanks, most should have the product completely switched over to 100% winter blends within a month. Mom and Pop operations could take a little longer.

[Formulabruce]

The Octane content doesnt mean much with alcohol as it is much LESS dense than regular gasoline. This is why engines which run any alcohol run Hotter , and higher RPM to do the same work as a gasoline running engine. The Miles per tankful on the window sticker tells the story. Usually a car or truck on a E85 diet gets 100 LESS miles per tankful..
A significant portion of alcohol ( from Grains) is not being made into hand sanitzer at $25 bucks a gallon ( up from $5 last fall) ..

[Schurkey]

There's fewer BTUs per gallon of alcohol vs. gasoline; and the flame temperature of alcohol is lower than the flame temp of gasoline. Why would an engine run hotter on alcohol?

In fact, they run cooler on alcohol.

[Dragncar]

Alcohol engines run cooler period. A lot of solid block guys run alcohol, wonder why ?

[charlie66]

Its funny how alot of people say you get bad mileage with e85. Thats not been my experience at all.

[Formulabruce]

Originally Posted by Schurkey

There's fewer BTUs per gallon of alcohol vs. gasoline; and the flame temperature of alcohol is lower than the flame temp of gasoline. Why would an engine run hotter on alcohol?

In fact, they run cooler on alcohol.

Runs Hotter because it actually has to burn MORE fuel to do the same amount of work.
Easy example is a window sticker on a New 1/2 ton flex fuel truck.
Gasoline with 10% alcohol vs E-85
Max range with E85 is around 100 Miles LESS than gasoline.
Flame temp can be low because it has way less density than Gas. This also means that it cant do as much work with same amount of fuel.
Note you never see E85 generators?
On a 1/4 mile car, fuel economy isnt an issue and they like being able to run 12:1 CR on a "Less dense" fuel.
The blends tend to be LESS volatile than gasoline with a reduced chance of explosions in accidents. < less volatile= Higher CR and more spark is needed.
Highly corrosive.
I have tried to make this easy to understand.

[Schurkey]

YES, fuel economy suffers with alcohol-blended fuel. We agree that there's less heat value in alcohol than in gasoline.

NO, engine temperature does not increase due to alcohol-blended fuel. Engines tend to run cooler on alcohol, or alcohol-blended fuel.

[johnta1]

As Schurkey said, alcohol runs cooler than gasoline because of the higher Latent Heat Vaporization.
Ethanol is used in modern cars because it's 'friendly' to the O2 sensors compared to methanol. With the higher Latent Heat Vaporization it takes more heat from the engine to make the alcohol work. Also the alcohol usually needs higher ignition timing. (plus higher CR to make more HP than gasoline only)

The problem if the engine is running hotter from the alcohol is the tuning is way off. The jetting if carbed will need to be a lot richer, the timing needs advanced. So probably a retarded timing and the lean mixture would make a very hot engine and probably not much HP.

EFI is great for this because the computer can adjust everything quickly.

[Tom Vaught]

Charlie 66 with his 200 cid 4 cylinder Turbocharged engine on E-85 made 800 hp
with 26 degrees of timing (with 38 psi of boost)

Luhn Performance made 862 HP at 5300 rpm and was running fine.
Then the dyno operator talked him into adding 2 degrees more timing (vs 27 degrees)
and he killed a head gasket. So I disagree with this "you need to add timing bs
to make HP on a boosted Pontiac engine. Notice this is with boost.
Timing is a variable on a NA engine, the rules are different on a boosted engine or NA engine using E85 fuel. Generic statements vs tuning for each fuel and engine combination kills parts.

Tom V.

[Formulabruce]

Originally Posted by Schurkey

YES, fuel economy suffers with alcohol-blended fuel. We agree that there's less heat value in alcohol than in gasoline.

NO, engine temperature does not increase due to alcohol-blended fuel. Engines tend to run cooler on alcohol, or alcohol-blended fuel.

Ok, going up a 5% grade, a gas engine runs at 3k, a e85 engine, same engine, will need 3,500 rpm. More fuel used, more BTU .
I am not saying it will over heat, but it is definitely burning enough more to generate more heat. On a older cast iron engine you can notice the heat increase more.

[STEELCITYFIREBIRD]

Wow, a lot of misconceptions on alcohol based fuels.

And not directed at any one person.

[jerry455]

The last car I owned that was E85 compatible was a 2009 HHR with a 2.2 Ecotec. It was rated at 155 hp on E10 and it was rated 160 hp on E85. I remember it was either the owners manual or window sticker that had that statement but it was surprising. Obviously you could not tell the difference but it was interesting.

[Scott65]

Originally Posted by STEELCITYFIREBIRD

Wow, a lot of misconceptions on alcohol based fuels.

And not directed at any one person.

This

[Sirrotica]

Alcohol (methanol) fueled sprint car engines have water preheaters so they can warm the engine before it's fired, simply because with only running 2-3 laps before the green is thrown, the engine is not up to operating temperatures. The oil is also not up to operating temperatures without preheating the engines. The same engines using gasoline will reach operating temperatures much quicker.

In the fall, or early spring the engines are difficult to start when the ambient temps are 30-40 degrees and won't fire without being primed with a squirt of gasoline in the 8 stack injectors before pushing off the cars.

Alcohol fuel does not reject anywhere near as much heat through the cooling systems as a gasoline fired engine does. As has been said already, if the compression ratio is not upped, and the fuel is not enrichened, alcohol will not produce anywhere near the torque or horsepower as the same engine using gasoline.

Tuning is nowhere near as critical, and an overich alcohol mixture has little affect on power compared to gasoline.

Anyone explaining that methanol "burns cool" is actually talking about the enthalpy or latent heat of vaporization of the fuel. When a liquid changes into a vapor (as it does in an internal combustion engine) heat energy is required for this transformation. And since heat is the enemy in engines—leading to all sorts of problems like an overtaxed cooling system, detonation, and even melted pistons—the more heat energy a fuel can suck out of the combustion process, the better.

Gasoline, when it undergoes a phase change can suck out about 150 BTUs of heat energy per pound of fuel, which results in a temperature drop. Methanol, on the other hand, takes 506 BTUs per pound of fuel of heat energy to make the phase change. When we look at our above example of an engine flowing 1,000 cfm of air, the 5.6 pounds of gasoline will take about 840 BTUs of energy, versus 8,855 BTUs for methanol—more that 10 times as much. This is what makes methanol such an effective fuel in forced-induction applications like turbocharging and supercharging, and it absorbs so much heat that an intercooler often isn't even needed.

[chiphead]

How well would e85 work on the fuel side of a plate nitrous system? If I ran 93 pump gas in the main tank and e85 in a separate fuel cell, how hard would that be to tune? I assume I would need to test alcohol content and tune for E60?

[Cliff R]

"So i went up to the BP station where the E85 was 95% 2 weeks ago and 90% last week and tested it today . It was 84% now.."

Let me know when it hits 100 percent and we'll drink it instead of burning it in our cars!.....LOL....

[Formulajones]

Originally Posted by chiphead

How well would e85 work on the fuel side of a plate nitrous system? If I ran 93 pump gas in the main tank and e85 in a separate fuel cell, how hard would that be to tune? I assume I would need to test alcohol content and tune for E60?

Trying to do that with a carb?? Very!

For something like that I would absolutely want sensors in the tank, and an EFI system that is capable of knowing ethanol content at all times. Otherwise you'll be wearing that carb out taking those bowls off all the time. Helicoils are in your future, lol. As has been mentioned numerous times already, the ethanol content is all over the place, all the time.

It's hard enough to tune an NA engine and keep up with changes, let alone one with a power adder. Toss in just using E85 on the fuel side of the plate and running regular E10 in the tank?? I don't know if it's been tried, I'm guessing it has, but it sure sounds like a hodge podge disaster waiting to happen if the tune is the least bit off.

Would be more manageable if you bought your E85 in drums and you knew exactly what you were putting in the tank.