MPG difference btw. E10 and E0 gasoline?
 

Has anyone documented any change in their MPG by switching from the E10 gas that's available everywhere to the straight stuff (E0) without alcohol? Percentage increase? Driveability? Let's hear all your stories!

I've been experimenting with this. No reasonable data yet as other variables like temperature and weather are having a greater affect on my numbers.

My first tank of E0 bumped me from 41 to 47. I was stoked but I can not account for how much the E0 helped as that week warmed up a bit from single digit temps, and I noticed my driving technique was better also.

My second tank E0 again went up to 49 but, again warmer and I was paying attention to driving more because of the improvement.

3rd tank I went back to E10 expecting to see a drop. But, No. Stayed at 49.

I do believe my car likes it but I will have to do more controlled runs with better data collection like temps to measure any difference. In the meantime I should at least see the average start to come back up. In the spring time. Due to the weather. :-P

I put 5 gallons of e85 in my tank of 10 gallons half of which was e10 and I want to say mpg went up as well as performance.

I saw upwards to a 10mpg increase,but that was a difficult test to repeat with all this cold wet, frozen weather on the east coast.

I think its due to more of the octane rating vs ethanol.

It's hard to make an accurate test just driving tank to tank because of all the variables. Plus, E0 is only available in premium as well so octane is higher. I tried a few tanks of premium but I have not been able to confirm any significant change on a tank by tank basis, so I have not made a change to premium.
What I can say is this province only officially made the change to E10 regular a couple of years ago, before that we were getting straight gas as far as I know. In the last two years my annual mileage has dropped 3-4% Considering premium is 10-12% more expensive, I see no advantage.

Premium does no benefit if your car doesn't require it. Higher octane definitely doesn't increase mileage.
However Ethanol has less energy than gasoline. E10 has 10% of this. So every ten gallons of fuel, you are putting in one gallon of ethanol.
Older cars like mine don't know what to do with ethanol in their system. Newer flex fuel cars can sense when ethanol is present and change accordingly.
As it has been stated....hard to measure the difference without tight control over the test.

This was the very reason I tried e85. I heard a car needs more fuel as e85 contains less energy so you burn more. Others say e85 makes more oxygen in the exhaust stream so your car leans out the afr and performance suffers. Others say e85 has the octane of 110 so for a high compression engine it will rock. How can it rock if its going to run lean? :eek:

Anyhoo I got an instant 9mpg, the engine seems to be quieter and the ima system acted as one would think. I refueled at half a tank and confirm the mpg increase during a brief spell of room temperature weather.

When the weather was a high of 32 and 70 miles I managed a dtc for lean condition.

I've found that economy differences with E0/E10 depend on the engine.

I can buy E10 at about $1.50/litre, or E0 at plus 2 or 3 cents/litre. They're both 91 RON octane.

I found E0/E10 made little difference in "BoB" - 88 Mitsubishi 4G37 with a carby.

Same story with "Zed"- 81 Nissan L28 with EFI.

On the other hand, Baa - 98 Mazda BP-ZE with EFI, gives enough FE increase to more than cover the extra cost of E0.

I guess you weren't looking for a "try it and see" answer, but that's what I'd advise.

I had always believed E10 would perform worse mileage wise as well until I saw this (trying to find a BSFC map for a K11 Micra) >

http://eprints.hud.ac.uk/8225/3/Fiel...ionEthanol.pdf

Doesn't make sense.... :confused:

From memory, the reason given for E10 being 2% cheaper than E0 when it was introduced in Australia, was the expected 2% reduced fuel economy.

Maybe cars produced after that, like the Micra used in this 2010 study, are specifically tuned to run better on E10?

My mileage is 8.5% better on E0 v. E10 (same octane) in the corolla. In the Civic its 11.9% better. This is over 4000 miles of driving alternating fuels in the Corolla, and 3500 in the Civic. The civic is higher than normal due to being able to stay in lean burn longer.

Reason:
Innovate Newsletter:

Tuning Tip: Ethanol Content

We've had a few reports where users could not “nail down” their tune on the street with the LM-1. The AFR's would jump about 0.5 AFR across the WOT band even in the same weather conditions in the space of a few days. Instead of holding a tune, the engine seemed to slowly “yodel.”

Naturally the first thing to blame was the LM-1. But it turned out that the users filled up at different gas stations, sometimes filling up on gas that had 10% ethanol mixed in. As expected, when Schnapps is mixed with cars, things get a little complicated.

If ethanol (stoich AFR of 9) is mixed with gasoline (stoich AFR of 14.7) the resulting gas has a lower stoich AFR than 'pure' gasoline. As the fuel injection is tuned to mix a certain amount of fuel for a given amount of air, the resulting mixture would be leaner when using a fuel with lower stoich AFR.

This can be calculated:

sAFR = (%ofAdditive * sAFRadditive + (90-%ofAdditive) * sAFRgas) /100

where:
sAFR is resulting stoich AFR
%ofAdditive is amount in % of mass of additive (ethanol) mixed in
sAFRadditive is stoich AFR of additive (9 for ethanol)
sAFRgas is stoich AFR of base gasoline (14.7)

For a 10% mixture of ethanol to gasoline by mass the resulting stoich AFR is 14.13

So, for an engine that's tuned to certain AFR at a certain load and RPM on straight gas, the resulting (gasoline equivalent) AFR when running the mixture can be calculated as:

new AFR = tuned gas AFR * (gasoline stoich ratio) / blend stoich ratio

An engine tuned to 12.5 gas AFR will run at the equivalent of 13 gas AFR with a 10% ethanol blend. This is what these people were seeing.

Of course, when running in closed loop, the engine will run at 14.13 AFR instead of 14.7. O2 sensors (incl. widebands) don’t measure AFR, but Lambda. Lambda is defined as actual AFR/stoich AFR. It's a ratio. In closed loop part throttle the engine is just running at Lambda 1.0, regardless of fuel. The same would be true for other Lambda values when running closed loop at WOT using a wideband. The engine would run at the tuned Lambda and everything would be fine. Open loop systems would need to be retuned for alcohol blends though.

Until next time... Keep On Tuning!

-Innovate Motorsports

i have a problem with their conclusion #2, that ethanol E20 produced higher torque at all speeds,etc. This statement makes me think that they don't know how an eddy current dyno operates or how to interpret the results.

My point is that an engine does not produce torque based upon its speed, but that the speed an engine turns is a function of the torque load on the shaft, the throttle opening, the spark advance, the fuel pulsewidth timing, etc. Speed is not an independent variable, but a result that depends upon the input conditions. Torque is the load on the engine and is not a function of speed.

On an eddy current dyno you set the torque load and it remains fixed at that torque regardless of speed. The engine throttle, fuel, spark, etc. are then adjusted to a set point, and then the speed is measured. Adjust to new set point, measure speed again. Collect data and plot torque on x-axis and speed on y-axis with family of curves for the different throttle openings, fuel timing, ignition, etc. They did not appear to do this in their testing.

I get about +1 MPG with non ethanol gas when it's available. Pretty significant seeing as this brings me from about 9.5MPG to 10.5 MPG.

We've got a 2003 Suburban 5.3 which has averaged 15.1MPG over its 185k mile life running on primarily e10. The few times it's had non-ethanol fuel run through it MPG increases by about 10%. Highway MPG has always been good with that car. It's not hard to consistently get 20MPG on e10 on trips loaded down with stuff running 55-70 mph. It goes down to about 19 MPG with the luggage carrier on top, and about 14 mpg towing a 4k lb dual axle trailer. It's been a good one.

I know what you mean about the e85. It usually really bashes MPG. But then again in many cases cost per mile is cheaper with it. Then you have the downfall of filling up more often too. In a Suburban like you're talking about, that's about 75 miles less to the tank running on e85. Not a big deal as long as you live in a populated area. I've talked to people out in the west (Wyoming, Utah) who won't run e85 because getting less miles to the tank can be a bigger danger when you can run roads for hours without ever passing a gas station.

I've rambled...

I knew ethanol was trouble. This just affirms it.

I've been noticing slightly rougher operation of my 5SFE engine while on E10.
I've noticed that it has reduced power output too.

I filled up one day with premo and it just felt better (had slightly more cajones at lower rpm/off from stop), the only difference however is in 1st gear, no other gears or speeds show an improvement, once it shifts up to 2nd the difference disappears.

It just feels wrong to me, I wrongly assumed/thought that I was doing something good for the environment while running on 10% ethanol, lower emissions, flowers out the tailpipe, etc.

I'll be running only 95 primo from now on methinks.

This is the typical Aussie viewpoint on fuel: http://theoldbloke.homestead.com/ethanol.html

This is what our pumps look like: (Not usually burnt out cars and firemen at them tho)
http://i.imgur.com/paBgfNC.jpg

I'm surprised that some of you all still have good access to non-ethanol blend fuel. Around here pretty much everything has been e10 for about a decade. I can find it a few places out into the country a bit, but I don't see it often. Oh, marinas also have it since it's better not to have ethanol in boats where fuel sits for a while. They tack close to a dollar onto the price though (about $4.60 for 93 octane).

That's the story in this part of the boondocks too. There's a local mom-n-pop luring folks in with E0, but it ain't cheap. I use it for the small engines (mower, snow blower, etc.) because it holds up well over time, and I ran a few tanks in my STi just for grins. The STi is noticeably less spunky on E0 91 octane than it is on Sunoco E(up to)10 93. But then it's turbocharged, and the STi folks who can get it seem to lovelovelove E85, so there may be something twisty going on there.

We have the "no ethanol" available in central Florida since so many people use it in their boats here, so I decided to try a tankful in my Festiva, even though it was about 60 cents a gallon more than E10.
After a 400 mile tank with negligible results, so I went back to regular unleaded after that. I have it documented somewhere back in my Fuelly.com records, but I definitely remember that I was not impressed.

I really hope we don't see anything more than e10 become mainstream soon. Older cars just can't handle but so much ethanol in fuel systems and engines that aren't meant for it.

Here's a comparison from 2012.

Unleaded vs E10—the comparison test | carsguide.com.au

NSW gov. has been going to end ULP (E0) availability since 2012, but the date gets delayed ... and delayed ... and delayed.
Now, after only having one local (small) service station selling ULP for a few years, two big chain service stations have started selling ULP again. I'm hoping it's a sign that ULP will continue for years to come. :D:D

The list of (Australian market) E10 compatible cars only lists Mazdas from 2005 onwards, so I shouldn't use it in Baa anyway. :)

I have 3 NA cars with many years of data with 87 octane 10% ethanol blends(E10), & many years of data with 87 octane 100% gasoline (E0). All 3 cars show mpg increases for E0 of 8%, 7% & 5%. All engines run smoother, quieter & with a trace extra low rpm torque, such that less downshifting is needed to ascend hills. 87 octane E0 is comprised of gasoline molecules averaging 87 octane(duh!). 87 octane E10 has ethanol molecules that average 114 octane of which 87 octane gasoline engines, as coming from the factory, are NOT designed to burn efficiently. ALSO, the gasoline molecules must average 84 octane, IF an average octane of 87 is to be created, while blending 10% ethanol. Yeah, even the 84 octane gasoline molecules aren't right for an 87 octane gasoline engine.

There is a difference of 3 percentage points in gasoline molecules, comparing 87 octane E10 to 87 octane E0, which doesn't include the ethanol difference. If your 87 octane gasoline engine isn't performing right with octane 87 E10..... try some 87 octane E0!!!

This is simple: gasoline engine engineers designed 87 octane gasoline engines to run best with 87 octane 100% E0. Ethanol engine engineers designed 114 octane ethanol engines to run best with 114 octane 100% ethanol. Ethanol/gasoline blends run neither gasoline or ethanol engines best.

By the math, should be a 3% difference. But EVERY hack on every forum always claims a 10% diff...

Since I only claim 8% to 5% E0/E10 mpg differences, am I LESS of a hack?
Good ethanol engine engineers designed high 114 octane, high compression ratio(16:1) ethanol engines to get the most energy AND work out of 100% ethanol. Ethanol, as used(but NOT burned efficiently) in low 87 octane, low compression ratio (9:1 to 12:1) gasoline engines, cannot give up energy & its work, nearly as efficiently. That is why adding only 10% ethanol to gasoline, lowers mpg 8% to 5%.

Already stated, is that 87 octane E0 is 87 octane(& is NOT BASE octane 84 mixed with high octane premium to average 87 octane). But 87 octane E10 is a mis-brewed mix of 114 octane ethanol AND 84 octane gasoline molecules, neither of which perform optimally in 87 octane gasoline engines designed to burn 87 octane gasoline at its best.

10% ethanol fuel has been a fact of life here for around a decade or more. I tried E0 in my 2011 Fiesta and at 80 cents more a gallon and 60 miles out of the way the mileage needed to increase by a little over 25% at that time when it was pushing $4 a gallon versus $3.20 for regular E10.

In sealed systems I have seen E10 go over a year without issues and my Honda pressure washer started fine after sitting for close to 6 months all with no additives.

E10 is one of the reasons we are importing much less than the 50+% of the crude oil we were importing before the mandates. I am neither and ardent advocate or opponent, and I understand the principles involved in choosing that renewable option, over crude from unpredictable sources.

Most EFI cars have no problem with E10, my 23 year old Sentra runs fine on E10, in fact the cheapest E10 I can find, without a hiccup, but EFI systems are much better equipped to handle the lower energy content than carbs and non feedback systems.

It's great to have fuel choice for old cars, trucks, lawn tractors and yard tools.

I'm on my second tank of 87 octane E0. Not sure if I'll go for a third.

Slambo saw a jump on the first tank from 39.7 to 42.8, but that may be partially due to the warmer temps.

Slambo! - #AintFuelin (Honda Civic) | Fuelly

E0 is not available in NJ. I have to drive nearly three hours round trip to Allentown, PA to fill up. It's $1 per gallon more than the least expensive top tier 87 octane E10 is locally.

The only reason E10 is cheaper than E0 is subsidization. So we pay less for gas, more for food, and our tax dollars go to enrich corn farmers instead of other activities where they might do more good.

As for importing oil - we don't need to do that anymore. Whether or not we should is another question. But it can no longer be said that adding ethanol to gasoline is reducing our dependency on foreign oil; technically we have no such dependency.

like many stated, to many variables between different cars and engines to give an accurate MPG loss with e10. it will effect some more than others.

now, e85, will drop MPG compared to e10 or e0 in any car. but, if your car is tuned for it, and the fuel system can handle it, you can have major performance increases. A buddy has a turbo charged Cobalt and runs E85, makes over 400 WHP with it. if he tuned on straight gas hed be making a lot less.

that being said, Im not a fan of ethanol at all mostly because i ride a 2 stroke sled and its hell on them things. even my carbed 4 stroke quad, I have to drain all the gas from the carb before putting it away for the winter or it will just make a mess in there.

Direct subsidies yes. Hidden subsidies no.
Renewable Fuel Standard - Wikipedia, the free encyclopedia

Is there an MPG difference?
It depends on the vehicle.
The 4.6L gas murdering town car we had could not tell the difference between E10 and E0.
The 1.8l turbo in the bug gets worse MPG on regular, I only have E0 RUG here. Comparing E10 mid grade or premium gas and E0 RUG is not a valid comparison.
The Hyundai always gets better MPG on the E0 gas than the E10.

The EPA & "ethanol in gasoline industry" forced & suppressed E0 to rarity. E0 is impossible to get in most big cities. Also, penalties can be imposed if oil companies go short on 100% ethanol-free gasoline to blend with ethanol. Lately, EPA may be light on this last requirement. Anyhow, E0 rarity drives up E0 price.

I ended my E0 testing after two tanks. The MPG gain was near expected (in the 3% range). The financial/time cost (+$1 per gallon/3 hour round trip to fill up) did not justify continuing the test. I will revisit it at a later date.

E0 is fabulous for old lawn mowers, weed wackers, motorboats, and classic cars. But it offers no cost advantage for modern vehicles (that have been designed to run on E10).

I ended my E0 testing after many years of E10 usage & many years of E0 burning for 3 cars. The MPG gain was NOT near expected(in the 8%, 7% & 5% range).

Glad it worked out for you! For me, it was a waste of time and money. :)

Try some 93 octane with Marvel mystery oil, my civic loves it better than e0 91 octane.

I think we talked in another thread but the inconvenience to get E0 was not worth my time

The marvel mystery oil comes in a 32 oz jug for $5.99 and you add 6 ounces per tank. The jug fits perfectly in the back seat cup holder in the civic.

Aye, yup! :) My HX is very happy on MMO. I run it fairly often. I've only run a handful of tanks on premium. I was thinking about throwing a gallon or two of E85 in, just for hoots (cheap octane).

Wish I could bolt a turbo on it …

I put some MMO in the camaro which is known to dribble gasoline out of the tail pipes at idle and with mmo it no longer does that.

I've tried it in my truck and the camaro but noticed no difference, but the first tank of gas with mmo in the civic was like it gained 10 horse power. I've had Lucas in it, rxp, but the mystery oil is the one that made the most difference in the civic