Are any of you noticing a fuel economy impact running E10?

Soldato
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Possibly a slight drop but nothing too significant (M140i). Will try and go back to alternate vpower/normal tank cycles though
 
Soldato
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Not noticed any change here, Ford Fiesta (2020 model iirc) 70mile round commute, 20% city, 20% motorway, 20% a/b road.
What about the remaining 40% of the journey?:D

My driving style is too inconsistent to do meaningful comparison, but it seems to be in the right ball park so it's all good on my end.
 
Soldato
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I could pick any 500 mile section and I suspect it will be at least 5% different from any 500 miles preceeding it or following it.

Apart from the obvious spikes in mileage, my journeys are actually very consistent.

I have a similar chart for my last car (which averaged more like ~33 mpg rather than the ~24 below)

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Soldato
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I'm still waiting for a rebuttal to any and all of my rebuttals, No direct answer to anything I've said, just side tracking and attacking. The favoured tactic of the fool.
But that's right. I must be the one to lack intelligence because I stated anecdotally I got a 25% mpg reduction in my TFSI TT!

So, what driving style did you use prior to the E10.

Mix if urban and extra urban? Exact same roads and mix prior to topping up?

You said "topped up with e10", was that a full tank from empty or a simple topping up.

How did you work out the MPG? If you only topped up, you can't even do the calculations required.

As you are so darn defensive about your numbers, please back them up with something more.

Also, I'd respect you based on what you have accomplished?

Sorry, but that's not how respect works. I couldn't care if you went to the moon, or cured cancer. My response and honest feelings would be "that's nice, well done...". I'd not personally feel any additional respect.

Ones personal accomplishments != gaining others respect.

How you treat and act around others is how you gain respect, and so far your reponses being what they are.. hmm. You get the idea.
 
Soldato
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know idea how legit this is, but bare in mind its the US fuel

That's a great economy test with a repeatable load. 4% difference between E10 and pure gasoline. Almost exactly as you'd predict. Ethanol has about 2/3rds the energy density of gasoline which means E10 should have 3.3% less energy than pure gasoline.

Halve that number to go from E5 to E10.

That channel is also brilliant. Have watched so many videos from it previously.
 
Soldato
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I thought they'd been running on this crappy fuel in Europe for years as their default fuel? Makes me think, my car that doesn't really run as nicely on E10... was more popular in Europe... and YET it's on the list as not compatible... so makes me think what about all the Europpeon who run my car since 1997 lol. hey ho, I don't care just user E5 instead just costs me more is my only gripe, but then again EVERYTHING costs more in 2021/2022 so what difference hey lol
 
Soldato
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That's a great economy test with a repeatable load. 4% difference between E10 and pure gasoline. Almost exactly as you'd predict. Ethanol has about 2/3rds the energy density of gasoline which means E10 should have 3.3% less energy than pure gasoline.

Halve that number to go from E5 to E10.

That channel is also brilliant. Have watched so many videos from it previously.
So by using that same logic would you see a 27% drop between running E5 and E85?
 
Soldato
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So by using that same logic would you see a 27% drop between running E5 and E85?

It was ages ago, but one of the American outlets ran such a test and that was pretty much exactly what the outcome was, in a flex-fuel car – a circa 30 per cent drop in economy from E5 to E85. There were similar reports to back up that outcome mentioned in it.

Not looked at such a thing since mind, and this was a while back.
 
Associate
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So by using that same logic would you see a 27% drop between running E5 and E85?

Yes, because you have to use a lot more of it as it has a lower energy density. The upside is if you tune for E85 you have a lot more power potential due to its higher knock resistance.

IIRC in the US ethanol is subsidised so at the pump E85 is a fair bit cheaper, so the lower economy doesn't matter.
 
Soldato
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It was ages ago, but one of the American outlets ran such a test and that was pretty much exactly what the outcome was, in a flex-fuel car – a circa 30 per cent drop in economy from E5 to E85. There were similar reports to back up that outcome mentioned in it.

Not looked at such a thing since mind, and this was a while back.

Yes, because you have to use a lot more of it as it has a lower energy density. The upside is if you tune for E85 you have a lot more power potential due to its higher knock resistance.

IIRC in the US ethanol is subsidised so at the pump E85 is a fair bit cheaper, so the lower economy doesn't matter.

Interesting stuff, I guess if the price offset is enough then it wouldn't matter from a cost point of view but the psychological impact of getting less miles to a tank and the added inconvenience would probably put people off it.
 
Associate
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Interesting stuff, I guess if the price offset is enough then it wouldn't matter from a cost point of view but the psychological impact of getting less miles to a tank and the added inconvenience would probably put people off it.

Its very popular in the enthusiast car community because its relatively cheap power for turbocharged or supercharged cars. Here's a couple of examples:
https://www.hpacademy.com/blog/how-much-more-power-can-you-make-on-e85/
https://www.garrettmotion.com/news/...ce-for-your-turbo-sammit-1-6l-miata-gtx2867r/

You may need a modify the fuel system to support it - you need to use more E85 by volume so you may need a higher flowing fuel pump, larger injectors and whatever else is needed to support that on the specific application. On older cars you may need to replace fuel lines and other fuel related items for ethanol safe stuff.

E85 was offered in the UK at the pump some time ago but it never took off and was withdrawn not that long after introduction. You can still get it but its comparatively expensive here.
 
Caporegime
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The issue with E85 is around stoich too. Due to the extra oxygen molecule the air to fuel ratio needs to be around 9. Rather than 14.7 of unleaded fuel. Hence more fuel per volume of air. This would normally result in more power but the lower energy content balances it out. Hence the power output is similar for the same engine setup but the higher octane allows the timing to be tuned further unlocking more power.
 
Permabanned
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That's a great economy test with a repeatable load. 4% difference between E10 and pure gasoline. Almost exactly as you'd predict. Ethanol has about 2/3rds the energy density of gasoline which means E10 should have 3.3% less energy than pure gasoline.

This thread is now utterly boring.
Congratulations.

I got ******* 18MPG into work today, with absolutely zero traffic.. I normally get at least 24MPG.. and funnily enough I had to nip into Asda to top up the last night, I only stuck £10 in - I had to as my car was on fumes but again my mileage is below 20MPG in the same conditions with same driving style.

TFSI NO LIKEY E10.

**** your science! It's as skewed as your eyesight!

NERDS!
 
Soldato
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This thread is now utterly boring.
Congratulations.

I got ******* 18MPG into work today, with absolutely zero traffic.. I normally get at least 24MPG.. and funnily enough I had to nip into Asda to top up the last night, I only stuck £10 in - I had to as my car was on fumes but again my mileage is below 20MPG in the same conditions with same driving style.

TFSI NO LIKEY E10.

**** your science! It's as skewed as your eyesight!

NERDS!
Dude time to get a new car by the sounds of it. 18mpg is just lame.
 
Permabanned
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So, what driving style did you use prior to the E10.

The same, I drive with my MPG monitor always active and I always watch what I'm doing to avoid waste.
I have autism, and I'm weird with numbers.. I can literally see the difference in the MPG monitor running E10.

Mix if urban and extra urban? Exact same roads and mix prior to topping up?

All urban, on both occasions, my car is only used to commute to work and back so my mileage each week remains the same. As I drive watching the MPG monitor and being very careful with my right foot. I know that a difference in driving style is not a possible reason for the difference I am seeing.

You said "topped up with e10", was that a full tank from empty or a simple topping up.

I did top up last night with £10 of E10 to an empty tank and noticed lower MPG this morning.. I know there's still some other fuel in the system but the majority is now E10.
When I said 'topped up with E10' what I should have said was car was ran till empty and I put a full tank of E10, as that's what happened with both of the FULL tanks I put in.

How did you work out the MPG? If you only topped up, you can't even do the calculations required.
I'm working this out on the obvious differences I can see from the trip computer when either fuel is put in. On every tank I reset all trip computers IE average speed MPG and monitor what I achieve for the following month. This is how I know my differences are not due to driving style as that doesn't change.

As you are so darn defensive about your numbers, please back them up with something more.
I said it was an anecdotal experience and should be taken as such, that said, I have a predisposition to believe real world experience over lab results, given my complete understanding of how corrupt both humans and our energy industry is!

Also, I'd respect you based on what you have accomplished?

Well.. I don't really want to go into it too much, its all very personal you see! I'll just say I've had a much harder life than practically anyone I know, I've spent more Christmas' and Birthday's alone than anyone should, I have no reason to pick myself up each day but I do, and not only that, but in spite of everything and everyone I lost, I achieved my childhood dream of becoming a K1 world champion.

When I say you'd respect me, you would, because my presence would intimidate you as it does all others. (even fighters and sparring partners)

We aren't all built the same!

Have a great weekend <3

EDIT. For what it’s worth.

Both tanks of E10 got me 210 miles. Before the switch I was getting 280 miles per tank.

But sure, despite my experience with cars and driving, it’s probably just the weather!
 
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