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A question relating to ethanol

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#1
Hey guys
From the UK here we have 99 ron equating to your 93

We have shell who do a 99 with 2.5 percent ethanol

Esso 99 with no ethanol

Now my understanding is that no ethanol would be best however my st has always been ran on a tiny amount of ethanol
Would the fuel trims sort this out themself?
Also apparently ethanol has a acooling effect however at such a low ethanol percentage would it even make a difference

The UK at forums are useless

Thank you guys
 


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#2
idk about in the UK, but from my understanding here in the US the guys (especially if you're tuned) prefer the most ethanol possible. that's why so many guys suggest an e30 tune if you have any close to you

maybe someone more familiar with the fuel in the UK can chime in
 


FiestaSTdude

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#3
Hey guys
From the UK here we have 99 ron equating to your 93

We have shell who do a 99 with 2.5 percent ethanol

Esso 99 with no ethanol

Now my understanding is that no ethanol would be best however my st has always been ran on a tiny amount of ethanol
Would the fuel trims sort this out themself?
Also apparently ethanol has a acooling effect however at such a low ethanol percentage would it even make a difference

The UK at forums are useless

Thank you guys
Here in the US, most gas is E10. Ethanol won't hurt your car, in fact it can give you a little more torque from what I understand. I'll sometimes add a gallon of E85 to my tank while on a 93 stage 1 tune. Also, lots of people run E30 or E40 tunes to benefit even more from ethanol.
https://www.fiestastforum.com/threads/driving-with-e30-on-a-93-oct-tune.21570/page-2
Here's a thread that I recommend you read through.
 


SteveS

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#4
Ethanol is not harmful to the car, as long as the fuel system has been designed with ethanol in mind, which the Fiesta has been.
Gasoline with no ethanol has higher energy density than gasoline with ethanol, so given the same octane rating, fuel without ethanol will have better fuel mileage, and in some cases, can make more power.
However, ethanol is an octane booster and also has a cooling effect in the cylinder. So especially with boosted engines, it is possible to tune for more boost with higher amounts of ethanol.
 


OP
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Thread Starter #5
Here in the US, most gas is E10. Ethanol won't hurt your car, in fact it can give you a little more torque from what I understand. I'll sometimes add a gallon of E85 to my tank while on a 93 stage 1 tune. Also, lots of people run E30 or E40 tunes to benefit even more from ethanol.
https://www.fiestastforum.com/threads/driving-with-e30-on-a-93-oct-tune.21570/page-2
Here's a thread that I recommend you read through.
Hey man read that thread
We do not get higher than 5 percent ethanol over here and thats on low grade fuel
So the only option is no ethanol or 2.5 percent
 


OP
L
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Thread Starter #6
Ethanol is not harmful to the car, as long as the fuel system has been designed with ethanol in mind, which the Fiesta has been.
Gasoline with no ethanol has higher energy density than gasoline with ethanol, so given the same octane rating, fuel without ethanol will have better fuel mileage, and in some cases, can make more power.
However, ethanol is an octane booster and also has a cooling effect in the cylinder. So especially with boosted engines, it is possible to tune for more boost with higher amounts of ethanol.
Hey man thank you
As we do not get over 2.5 percent over here would 2.5 percent over no ethanol really make any difference to the cooling side of things as all bigger turbos over here run with one of the two petrol stations listed
 


FiestaSTdude

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#7
Hey man read that thread
We do not get higher than 5 percent ethanol over here and thats on low grade fuel
So the only option is no ethanol or 2.5 percent
Ah ok. I would go with whichever one is cheaper because I doubt that 2.5% ethanol would make a difference.
 


gtx3076

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#9
In my opinion 2.5% isn't enough to worth bothering with. I've been running E30 for several years now never had an issue.
 


FiestaSTdude

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#10
Thank you buddy
Appreciated
Out of curiosity, do you have E85 in the UK at all? It would make sense if you didn't because I don't believe you product corn, at least not in the amounts we do over on this side of the pond.
 


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#11
These cars have been built to tolerate Ethanol, so there is NO NEED to avoid it. It's actually a good way to boost octane and you also get a small bit of a boost in cooling from evaporation.

BTW, I have a 1985 Monte Carlo SS that I purchased brand new and have been running 5 and 10% ethanol blends since 1985. The carburetor and fuel system have 248,000 miles on it and I have never had any issues with the carb. It's flat out proof that all that hype you hear about ethanol is Bull Shit. BTW, the current engine is a GMPP 383 and it does have some scoot. However due to the weight of the car I'm pretty certain my FiST would out do it in a 0-60 run, over 60 the Monte wins because these cars did have good aerodynamics and 345 HP does trump 197 at speed.
 


M-Sport fan

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#12
Ethanol is not harmful to the car, as long as the fuel system has been designed with ethanol in mind, which the Fiesta has been.
I have always wondered, ever since owning this car, and hearing of everyone running E30, E40, E50, or even straight E85 (and maybe even full-on 'racing' E98??) in their tuned, aftermarket snail, FiSTs, if our fuel systems and it's component materials were built to stand up to these high ethanol concentrations, or was it just built to a level/'point' in order to stand up to only E10/E15 fuels? [dunno]
 


FiestaSTdude

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#13
I have always wondered, ever since owning this car, and hearing of everyone running E30, E40, E50, or even straight E85 (and maybe even full-on 'racing' E98??) in their tuned, aftermarket snail, FiSTs, if our fuel systems and it's component materials were built to stand up to these high ethanol concentrations, or was it just built to a level/'point' in order to stand up to only E10/E15 fuels? [dunno]
In my opinion, we have enough people using E30+ that if it caused issues we would hear about it. I haven't heard anything yet, so I'm pretty confident it's fine.
 


SteveS

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#14
I have always wondered, ever since owning this car, and hearing of everyone running E30, E40, E50, or even straight E85 (and maybe even full-on 'racing' E98??) in their tuned, aftermarket snail, FiSTs, if our fuel systems and it's component materials were built to stand up to these high ethanol concentrations, or was it just built to a level/'point' in order to stand up to only E10/E15 fuels? [dunno]
If the seals are able to withstand ethanol, it's any level of ethanol. That's the primary problem with ethanol. In parts not designed for it, the seals would fail and leak. It's been a long time since you could buy a car in America that was not designed to withstand ethanol in fuel.
 


M-Sport fan

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#15
If the seals are able to withstand ethanol, it's any level of ethanol. That's the primary problem with ethanol. In parts not designed for it, the seals would fail and leak. It's been a long time since you could buy a car in America that was not designed to withstand ethanol in fuel.
Thank you, as that is what I was specifically questioning, i.e.; the "materials" of which the seals/hoses/softer components of the fuel system are made, and whether or not manufacturers would 'skimp' on these to save a few pennies for a grade which could NOT handle straight E85, save for their fully 'flex fuel' labeled/designated vehicles. [wink] [thumb]
 


SteveS

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#16
There is another issue for fuel systems which ethanol presents, and that is rusting of ferrous metals, since ethanol carries water. But since the 1980s all fuel systems are also made from metals which are not subject to corrosion from that either.

The final issue is not one of the cars, but of other fuels. There used to be some gasoline additive packages which turned to black sludge in the presence of ethanol. For a long time it was believed by people that this was the result of rubber hoses deteriorating from the ethanol, but it was not. They don't use those additives any more.
 


gtx3076

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#17
There is another issue for fuel systems which ethanol presents, and that is rusting of ferrous metals, since ethanol carries water. But since the 1980s all fuel systems are also made from metals which are not subject to corrosion from that either.

The final issue is not one of the cars, but of other fuels. There used to be some gasoline additive packages which turned to black sludge in the presence of ethanol. For a long time it was believed by people that this was the result of rubber hoses deteriorating from the ethanol, but it was not. They don't use those additives any more.
MS3's had "black death" that could seize up the HPFP cause a lean condition and grenade the motor, but that was only when people ran really high concentrations of ethanol. Fiesta's have been around for about 8 years now, I'm sure if there was risk of failing components we would have heard by now. I run E30 almost exclusively for almost 40k miles.
 


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#18
The net octane is the octane. If you have 5% Ethanol, and 99 octane, that is your octane rating.

Depending on where one lives, the most important thing about fuel is what blend they are selling in a given month. The seasonal blends matter in terms of energy and power. Winter blends drop power a few % points. Summer fuels in winter affect performance with hesitations, etc.

The number of regions and blends will hurt your brain. Use petrol from local suppliers, and if you're car isn't sitting 6+ months a year and is used regularly, go about your business, run the octane you're supposed to use, and call it a day.

Ethanol might, just might, matter the most at a cold, sloppy/rich start up, if you're gonna just idle the engine up to warm temps, because at that point, it could contribute more than non-ethanol fuels to washing the thin oil layer off the cylinder walls.

Nevertheless, with almost 2-million kms of driving experience, ethanol only ever mattered in boats and other vehicles which had a fuel system that isn't sealed, and the hygroscopic ethanol draws in water from the actual atmosphere. This has brought thousands, if not millions, of owners to their knees and to bankruptcy.

-- In cars? Meh. Go live.
 


M-Sport fan

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#19
Ethanol might, just might, matter the most at a cold, sloppy/rich start up, if you're gonna just idle the engine up to warm temps, because at that point, it could contribute more than non-ethanol fuels to washing the thin oil layer off the cylinder walls.
I suspect that given the same operational parameters as above, the high ethanol content fuel will also get past the ring land/packs easier than no ethanol fuels, and contaminate the oil in the sump, possibly quicker as well. [dunno]

The question is; does the ethanol 'burn off'/volatize out of the oil, once said oil is HOT, as quickly as the non ethanol fuels do?
Especially given it's propensity to absorb moisture (which can then wreak havoc on the oil with the resultant acidity/corrosion/etc.), as you have stated.
 


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