100% Ethanol vs. Premium gas

Civic 2016+ 1.5 Turbo
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turboroe
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100% Ethanol vs. Premium gas

Post by turboroe »

Considering that I install a flex fuel kit and run +6psi on my cvt:

1# Will it make more or equivalent power with 100% ethanol than with premium fuel?
2# Will it run as safe as with premium (with low knock count and low k. Control)?

3# any damage to my cvt if I use 100% ethanol and +6psi?


As I mentioned in other posts, premium gas is hard to find in Brazil, and regular gas is E27. In other hand, E100 is found in every gas station here and price is ok, so this might be an alternative to ditch the expensive premium gas.
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Hondata
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Re: 100% Ethanol vs. Premium gas

Post by Hondata »

1. Yes.
2. Yes.
3. Perhaps.

Ethanol will give more power than your local premium, but I do not think you want to run more than about 40% ethanol for a number of reasons.
- you will not get any more power after 50% ethanol, and there is little gain after 40%.
- fuel range is much lower
- your low pressure fuel pump might not like 100% ethanol. I do not know that the Brazil Civic can run on 100% ethanol, but for the US version 80% ethanol will dissolve the low pressure pump brushes over time.

As for the CVT they seem fine at +6psi but do not power brake a CVT ever. Even a stock CVT can be damaged in 10-20 launches this way.
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turboroe
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Re: 100% Ethanol vs. Premium gas

Post by turboroe »

Cool, thank you for the information.
I surely won't attempt a power brake after your advice.

So why do the flex fuel kits advertise the use of E85 if this will mess with my fuel pump brushes?

Our regular is already E27, then I should add ethanol to make it E50 and this should make more power than premium?
EFICU
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Re: 100% Ethanol vs. Premium gas

Post by EFICU »

turboroe wrote: Thu Jan 09, 2020 4:22 am Cool, thank you for the information.
I surely won't attempt a power brake after your advice.

So why do the flex fuel kits advertise the use of E85 if this will mess with my fuel pump brushes?

Our regular is already E27, then I should add ethanol to make it E50 and this should make more power than premium?
Flex fuel kits advertise the use of E85 because people will buy them and use them knowing the consequences of running that fuel. Same reason why companies sell turbo kits for cars that were never meant to be boosted. For a lot of people, they don't mind changing their fuel pump on a semi regular basis because of the corrosion from E85.

Yeah if Hondata says there isn't much to be gained over 40-50% ethanol, and you have E27, it may not even be worth it to go through the process of adding more ethanol. If you do want to get to E50 or so, I believe your car has a 12 gallon fuel tank? By my math, which may be wrong, you would want to put 10 gallons of your normal E27 in and 2 gallons of E100. That would give you an E47 equivalent if I am doing my math correctly.
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Hondata
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Re: 100% Ethanol vs. Premium gas

Post by Hondata »

I think it might be different in Brazil where regular has 27% ethanol. If you add ethanol to E10 pump gas to get E27, you will raise the octane and therefore power. But if the fuel starts at E27 then it probably has been blended with gasoline with a lower octane to give the same resultant octane.
So you'd have to experiment and see what the knock control does with each blend.
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turboroe
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Re: 100% Ethanol vs. Premium gas

Post by turboroe »

Can you tell me exactly what a flex fuel kit does in terms of the calibration? Is it just adding extra fuel, or does it change timing also?

Since i will be using only e27, wouldn't it be possible to make a custom tune for my e27, with added fuel, instead of installing a flex fuel kit?

I am really keen on installing some extra hardware while my car is still under warranty.
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Re: 100% Ethanol vs. Premium gas

Post by Hondata »

It alters the fuel & ignition mainly.

But if your vehicle is designed to run on E27 then it already has those alterations in the stock ECU so you won't see any advantage.
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