E85 mixed with 93
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2019 C43 AMG
E85 mixed with 93
My c450 manual says 91 octane minimum and doesn't mention E85 anywhere and not by the gas cap either. Is it safe you mix 93 pump gas with E85? And if it is, is there any benefit to stock performance before I get a JB1?
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Most forums will tell you it's safe to add up to approximately +/- 20% E85 in to a regular tank of 91/93. I regularly add up to 4gal or 23% of my tank. I did before my JB1 and continue to after.
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2019 C43 AMG
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The problem with ethanol has nothing to do with detonation, in fact the opposite is true.
There are two main problems with E85 EtOH based fuels running in 4 cycle engines:
1. EtOH is hygroscopic which makes it less than ideal for vehicles that aren't being used as daily drivers. Moisture from atmosphere readily goes into solution with E10-E85 fuels. The more EtOH the greater the affinity for H2O.
2. The other problem is the different solvent characteristics of alcohols as compared to gasoline. Alcohols are polar solvents that attack different kinds of rubbers and polymers than non-polar gasoline does. Most modern fuel systems have been modified to allow for some use of EtOH without causing damage, but E85 can completely FUBAR older vehicles if specific precautions aren't taken.
There are two main problems with E85 EtOH based fuels running in 4 cycle engines:
1. EtOH is hygroscopic which makes it less than ideal for vehicles that aren't being used as daily drivers. Moisture from atmosphere readily goes into solution with E10-E85 fuels. The more EtOH the greater the affinity for H2O.
2. The other problem is the different solvent characteristics of alcohols as compared to gasoline. Alcohols are polar solvents that attack different kinds of rubbers and polymers than non-polar gasoline does. Most modern fuel systems have been modified to allow for some use of EtOH without causing damage, but E85 can completely FUBAR older vehicles if specific precautions aren't taken.
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It certainly can:
https://en.wikipedia.org/wiki/Methanol_toxicity
https://en.wikipedia.org/wiki/Methanol_toxicity
