Zero ethanol gas fuel economy

[Ryland3210]

I had a good opportunity to compare MPG with 10% (New York) and 0% (Vermont) ethanol gas on my 5.7Liter EFI.

I averaged 15-20% better with 0% ethanol. This was while running several tankfulls of each on the same 700 mile cruise in Lake Champlain under very similar weather and cruising conditions.

Friends have report similar results in automobiles.


Mod EDIT: Lets leave the political discussions off this boating forum. Thank you

 

[Scott Danforth]

Yes it does

 

[airshot]

same thing in your automobile, the engine was designed to run on pure gasoline so the alcohol reduces power. On the other hand, if the engine was setup to run on alcohol then it would run crappy on gasoline. The reason cars get crappy fuel economy with e-85 is the engine is set to run on straight gasoline, if the engine were setup to run on strict E-85 only the power and fuel economy would be great just like the Nascar race engines. They are producing more power than ever on 20% ethanol......but they are setup to run that only. When the gov't mandates engines to run on a mix of fuel the public looses.

 

[H20Rat]

I had my previous car (2002 subaru WRX) tuned specifically to run on E85... Mileage was as good if not just slightly better, and I had a substantial boost in horsepower, and an even bigger boost in torque! (e85 is nicknamed rocket fuel in tuner circles!) With e85 in a modified turbocharged engine, you have the ability to crank boost up way beyond what gasoline is capable of, as well as pushing the timing quite a bit. E85 also burns cooler, I didn't have to watch the EGT gauge like a hawk during tuning like I did with gas. E85 has roughly 110 to 115 octane.

But.. as you found out, in an engine that wasn't designed for it, you really can't take advantage of it. Without variable compression (aka, a turbo or supercharger), there really is no way to make an engine that can run equally well on either fuel.

 

[thumpar]

A WRX turbo is a lot different than a boat engine. You could have accomplished the same thing with water injection as far as boost and temps go. That is how us old school turbo runners did it. 25lbs was just a start.

 

[dingbat]

Not a car guy. Can someone please explain to me how a 2% decease in available energy *(114,000 vs.111,836 btu) becomes 15-20% reduction in fuel mileage? I imagine the timing is the cause of some of the inefficiencies but 15-20%? Seems unlikely.

 

[bruceb58]

Not a car guy. Can someone please explain to me how a 2% decease in available energy *(114,000 vs.111,836 btu) becomes 15-20% reduction in fuel mileage? I imagine the timing is the cause of some of the inefficiencies but 15-20%? Seems unlikely.

Agreed. Ethanol has 30% less BTU content than gasoline. Since the max ethanol content is 10%, that translates to 3% less BTU content for 10% ethanol fuel.

Unless you use a flow meter and operate the boat under identical conditions, power settings...not a valid test.

 

[Scott Danforth]

in addition to the lower BTU setup, there are significant inefficiencies with the standard fuel/air maps that do not take into consideration the exact mix you are running at the exact time. couple this with the fact that a pump advertising 10% ethanol may have much more (up to 30% found in some stations in 2011), the consumer truly doesn't know what is being pumped out of the nozzle into the car (and neither do the engineers setting up the fuel tables)

I agree the OP's 15-20% may not be accurate, however I see a 10-12% increase in fuel economy simply by fueling up in different states other than F. This increase is similar to the increase I see with a tank of E0.

 

[gm280]

Let's face it, no boat gets good gas mileage. It isn't one of their strong points. You pay to play!

 

[Scott Danforth]

Let's face it, no boat gets good gas mileage. It isn't one of their strong points. You pay to play!

agreed, if you want economy in a boat, it has oars or a sail

 

[Bondo]

Let's face it, no boat gets good gas mileage. It isn't one of their strong points. You pay to play!

Ayuh,.... 'n since Non-ethanol has been available 'round here for a few years now,.... I'm Gladly payin' a premium for it,...

It's the only gasoline I buy,....
Boats, chainsaws, power equipment, All of it,....

Don't need any "Tests",... lots less carb/ fuel delivery problems now,...

Pickup is diesel of course,... wish the barge was,....

 

[Scott Danforth]

It's an $0.80 per gal premium here. Only $0.20 in other states. I keep the e0 for the small engines currently

 

[bruceb58]

And we can't get 0 ethanol at all so it isn't even something to worry about.

 

[airshot]

Non ethanol in my area is 3.79 per gallon where reg ethanol fuel is 2.29 per gallon. I can buy a lot of marine stabil for that difference.

 

[dingbat]

And we can't get 0 ethanol at all so it isn't even something to worry about.

only available at marinas. Based upon reviews of the local marine supplies, I take my chances.

 

[dingbat]

in addition to the lower BTU setup, there are significant inefficiencies with the standard fuel/air maps that do not take into consideration the exact mix you are running at the exact time. couple this with the fact that a pump advertising 10% ethanol may have much more (up to 30% found in some stations in 2011), the consumer truly doesn't know what is being pumped out of the nozzle into the car (and neither do the engineers setting up the fuel tables)

I agree the OP's 15-20% may not be accurate, however I see a 10-12% increase in fuel economy simply by fueling up in different states other than F. This increase is similar to the increase I see with a tank of E0.

Thanks for the info.

Only E10 in my area. it is what it is

 

[jbcurt00]

E zero, if available, can be found here:
Www.Pure-gas.org

 

[Silvertip]

same thing in your automobile, the engine was designed to run on pure gasoline so the alcohol reduces power. On the other hand, if the engine was setup to run on alcohol then it would run crappy on gasoline. The reason cars get crappy fuel economy with e-85 is the engine is set to run on straight gasoline, if the engine were setup to run on strict E-85 only the power and fuel economy would be great just like the Nascar race engines. They are producing more power than ever on 20% ethanol......but they are setup to run that only. When the gov't mandates engines to run on a mix of fuel the public looses.

You apparently don't understand how flex fuel vehicles (GM in my case) are set up. First, the engine management system knows what type of fuel is being burned through a sensor in the tank. It is also smart enough to know what the rough mix is. Second, knowing what the fuel type and mix is, the engine management system along with the knock sensors can advance engine timing to take advantage of the higher octane in E10 - E85 so as the "tuners" indicate, performance is better. So much for the crappy running -- that is simply not true. Injector pulse width is also adjusted since more fuel is required which accounts for the slightly lower fuel economy. Many on this forum have seen my posts on this topic and this one is rather timely since I just returned from a 2100 mile, 13 day road trip to Iowa, Nebraska, Wyoming, Colorado, and South Dakota. Residents of several of those states know the speed limits can be 75 (Nebraska/Wyoming) and 80 MPH (South Dakota). I drive a Chevy Impala 3.5 V6 flex fuel vehicle and on this trip burned the cheapest fuel available which ranged from 85 octane to E10 (no E-85 this trip). As I pulled in the driveway the trip computer showed exactly 29 mpg. Considering speeds, our load and mountain driving this is pretty darn good performance. EPA for this vehicle is 31 and under more normal driving conditions I have no problem reaching that number. When E-85 is about 35 - 40 cents/gallon cheaper than E10 I use it and do not experience the 20 - 30% drop many folks say they experience. That is probably because they are not actually doing a valid comparison and no two people drive the same way which has a huge effect on fuel economy. I might add this car now has 110,000 miles on it and other than replacing a water pump gasket and thermostat has had zero maintenance issues. My boats and collector cars have always run E-10, stored with protected E-10 and again I have never had an issue.

 

[bruceb58]

http://www.edmunds.com/fuel-economy/...ison-test.html

For their test, they found that the E85 had 26.5% worse mileage than E10 which is similar to what the BTU content difference is.

E85 basically has to be close to 30% cheaper to make it worth it. If you are paying $2.50/gallon, that means it has to be $0.75 cheaper to be worth it.

 

[Silvertip]

One test, one vehicle and not very scientifically conducted. E85 in my area is as much as $1.00 cheaper than E10 when E10 is anywhere above $3.00/gallon. 60 - 80 cents is common. Can't confirm or deny truck fuel consumption but my use confirms nowhere near the 25 - 30% reduction.