1994 vette E15?
Drifting
Joined: Apr 2020
Posts: 1,925
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From: Orange, CA
E15, as you asked, is a blend of crap unleaded gasoline (85 octane) with 15% ethanol, which nets a final octane rating of around 88 octane. Just as you would not want to put 87 octane fuel in your Corvette, you would not want to put E15 fuel in your Corvette. The ethanol content is not nearly as important as the octane rating in this specific case. E15 refers to a very specific fuel sold commercially. It's crap. Do not put it in your Corvette.
Here in California we have 91 octane at best, and it tends to be blended with up to 10% ethanol. Both my '94 and '95 handle this fuel just fine. As someone else already stated, the manual points out to you that using up to 10% ethanol blended fuels is perfectly acceptable as long as the octane rating is 91 or higher.
Last edited by Nomake Wan; Sep 24, 2020 at 04:49 PM.
Team Owner
Joined: Jul 2004
Posts: 28,465
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From: Hartford WI
IF the gas around you is E10, why are you trying to run E15 in your car? Not sure I understand the reason you ask. I'm not sure how much worse the E15 is vs the E10. I run E10 simply because I am not going to tie myself to a gas station that is out of the way whenever I need to fill. I fill, run the tank to near empty and fill when I can. IF I choose to run pure gas, I would have to top up at a place 20 mins away and be tied to only a few stations.
Drifting
Joined: Apr 2020
Posts: 1,925
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From: Orange, CA
IF the gas around you is E10, why are you trying to run E15 in your car? Not sure I understand the reason you ask. I'm not sure how much worse the E15 is vs the E10. I run E10 simply because I am not going to tie myself to a gas station that is out of the way whenever I need to fill. I fill, run the tank to near empty and fill when I can. IF I choose to run pure gas, I would have to top up at a place 20 mins away and be tied to only a few stations.
"E15" is actually a specific fuel, with a final octane rating of about 88.
Do not put E15 in a Corvette, just as you should not be putting 87 in a Corvette.
Team Owner
Joined: Jul 2004
Posts: 28,465
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From: Hartford WI
What is the specific effect of E15? Not sure what it is myself other than more than 10, less than 15 percent alcohol.
Drifting
Joined: Apr 2020
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From: Orange, CA
"E10" is what people colloquially refer to modern gasoline as. It does not refer to a specific fuel, it just means "up to 10% of the fuel content is ethanol."
Team Owner
Joined: Jul 2004
Posts: 28,465
Likes: 3,288
From: Hartford WI
Again, please try to understand. E15 is the name of a specific fuel. Think of "E15" as the same as "87," "93" or "E85." It refers to a very, very specific thing. If it helps your brain wrap around the concept, just think of E15 as 88. That is why you should never put it in a Corvette.
"E10" is what people colloquially refer to modern gasoline as. It does not refer to a specific fuel, it just means "up to 10% of the fuel content is ethanol."
"E10" is what people colloquially refer to modern gasoline as. It does not refer to a specific fuel, it just means "up to 10% of the fuel content is ethanol."
Race Director
Joined: Sep 2001
Posts: 14,676
Likes: 751
From: NEwhere Ohio
This thread is about E15. The person you were trying to call out for being an idiot was talking about E15. E15 is not a blend of 87 octane, it's 85% much-less-than-87-octane and 15% ethanol, which brings the final octane number to around 88.
Please understand the thread creator's question and the replies before trying to claim someone doesn't know what they're talking about.
Please understand the thread creator's question and the replies before trying to claim someone doesn't know what they're talking about.
nowhere did i call anybody an idiot
also nowhere did the OP state that he was using the type of E15 that is blended with 87 octane as a base stock.
all the gas pumps around me have stickers on them saying contains up to 15% ethanol. (And that includes 93 octane)
again my point was simply ‘his computer will adjust for it’. He’s not going to lean out and burn up a piston, for example - at least not at 15% levels.
Any ethanol is more corrosive - bc it attracts water. But is 15% enough to cause a problem on a regularly driven vehicle ? I wouldnt store mine (at 55% ethanol) over winter on a high content of ethanol. Id switch it back to 93 octane (and the 10-15% ethanol on it) - as well as the tune back to 93 octane which i swap myself via ostrich connected to the chip/ laptop computer
to aklim’s point;
i also didnt mention that I have installed 60 lb/hr injectors (wish i went bigger ) designed for Ethanol (or gas) fuels on my 93
no idea if the stock 1993 injectors would work (wouldnt be harmed) by ethanol. Real high ethanol concentrations and the stock fuel system /injectors may not be able to provide enough fuel. (Something like 30% more fuel volume needed on e85 vs 93 octane).
Last edited by dizwiz24; Sep 27, 2020 at 01:13 PM.
Drifting
Joined: Apr 2020
Posts: 1,925
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From: Orange, CA
OK. E15 has up to 15% alcohol. It is 88 octane. What I am trying to see is what YOUR objections to it is and not just "don't do it". For example, if you have Multec injectors, E10 will kill it sooner or later. The cure to it is to dump your Multecs and get Bosch and you are fine. If there is an issue/issues when you go from E10 to E15, feel free to explain. I don't understand "don't do it" or "it is bad" without some sort of explanation as to the effect and perhaps mitigation can be discussed.
E15 refers to a specific type of fuel with an octane rating of 88.
As this is less than 91 octane, do not put it in a Corvette. The ethanol content is a secondary issue to the octane issue.
If you re-read the OP, you'll find that he mentions that all the fuel around him has at least 10% ethanol in it, followed by asking if he can run E15. This suggests that the regular unleaded gasoline around him is like ours, and has up to 10% ethanol in it. To then ask about running E15 implies the presence of E15 fuel in addition to the existing fuel. And if you take 5 seconds to look that up, you'd find pages like these:
https://ethanolrfa.org/retailers/e15/
https://iowarfa.org/ethanol-center/e15/e15-faqs/
So there you go. Do not put E15 in a Corvette.
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Team Owner
Joined: Jul 2004
Posts: 28,465
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From: Hartford WI
Then you should have said "Do not use in any vehicle requiring 91 Octane.". IOW, don't put it in my 2020 MB that requires premium gas and not just corvette.
Drifting
Joined: Apr 2020
Posts: 1,925
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From: Orange, CA
OK. That was what I was trying to clarify. There are people that feel that E10 cannot go into a corvette even if it is 93 because the injectors will get messed up if they are Multecs or the performance isn't there, etc, etc. Would the 3 octane points harm the engine? I don't know. It's only 3 points and there is the KS that will take care of the knock that might occur under hard acceleration so there is that. Some think that the corvette is some sort of special car that requires special treatments.
Then you should have said "Do not use in any vehicle requiring 91 Octane.". IOW, don't put it in my 2020 MB that requires premium gas and not just corvette.
Then you should have said "Do not use in any vehicle requiring 91 Octane.". IOW, don't put it in my 2020 MB that requires premium gas and not just corvette.
Just put the proper fuel in.
Team Owner
Joined: Jul 2004
Posts: 28,465
Likes: 3,288
From: Hartford WI
But we're on a Corvette forum talking about Corvettes. As for relying on the knock sensors, that's not a great plan. Can you? Sure. But if your knock feedback system isn't working right you could potentially cause damage, and if it is working right you're going to lose quite a bit of power which will negatively affect your already-not-great gas mileage. It's not worth saving the few cents per gallon.
Just put the proper fuel in.
Just put the proper fuel in.
Team Owner
Joined: Sep 2001
Posts: 62,154
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From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
I would not run more than 10% ethanol in the car. I personally only run sugar free E0 in my 88 and I like that it gets extra MPG as a result. For longevity reasons you are better off sugar free, particularly if you store the car in winter. Keep the corn liquor in a jar.
However to run any grade that had 15%+ ethanol, and I understand E15 is a specific grade, you need to upgrade the entire fuel system to handle the ethanol. E15 if it were premium octane rated would be fine, but when you get to years of usage you will run into problems. Injectors, fuel pump, some of the soft lines, FP regulator. Look up the part upgrades necessary for E85 and most of that should cover your ***. Ideally you would then have the computer tuned to handle the higher ethanol gasoline if you only had higher ethanol content in your area.
However to run any grade that had 15%+ ethanol, and I understand E15 is a specific grade, you need to upgrade the entire fuel system to handle the ethanol. E15 if it were premium octane rated would be fine, but when you get to years of usage you will run into problems. Injectors, fuel pump, some of the soft lines, FP regulator. Look up the part upgrades necessary for E85 and most of that should cover your ***. Ideally you would then have the computer tuned to handle the higher ethanol gasoline if you only had higher ethanol content in your area.
Le Mans Master
Joined: Sep 2013
Posts: 6,192
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From: near the thumb in the mitten
The problem with E15 is it's beyond what the fuel.system was designed for. Back when the C4s were built ethanol enhanced fuel wasn't the standard. Ethanol was used mostly for moisture and fuel quality issues. The 10% was to allow for some fuel quality issues. In the 2000s fuel was reformulated to use ethanol vs MBTE(?). GM found the Multec injectors used in the corvette had problems with ethanol acting like a solvent. High concentrations can break down the plastics and adhesives use in the fuel system.
So there is an element of risk use high percentage of ethanol than what is attended. If fuel system is updated to E95 compatible, you could run from Prue Gas (E 0 ) to E85. Tuning maybe required depending on ethanol content, since it takes roughly 60% more E85 vs E10 gasoline for engine to run correctly. Simply don't use E15 use E10 or lower.
So there is an element of risk use high percentage of ethanol than what is attended. If fuel system is updated to E95 compatible, you could run from Prue Gas (E 0 ) to E85. Tuning maybe required depending on ethanol content, since it takes roughly 60% more E85 vs E10 gasoline for engine to run correctly. Simply don't use E15 use E10 or lower.
Melting Slicks
Joined: Jan 2014
Posts: 2,478
Likes: 254
From: Downers Grove Illinois
The problem with E15 is it's beyond what the fuel.system was designed for. Back when the C4s were built ethanol enhanced fuel wasn't the standard. Ethanol was used mostly for moisture and fuel quality issues. The 10% was to allow for some fuel quality issues. In the 2000s fuel was reformulated to use ethanol vs MBTE(?). GM found the Multec injectors used in the corvette had problems with ethanol acting like a solvent. High concentrations can break down the plastics and adhesives use in the fuel system.
So there is an element of risk use high percentage of ethanol than what is attended. If fuel system is updated to E95 compatible, you could run from Prue Gas (E 0 ) to E85. Tuning maybe required depending on ethanol content, since it takes roughly 60% more E85 vs E10 gasoline for engine to run correctly. Simply don't use E15 use E10 or lower.
So there is an element of risk use high percentage of ethanol than what is attended. If fuel system is updated to E95 compatible, you could run from Prue Gas (E 0 ) to E85. Tuning maybe required depending on ethanol content, since it takes roughly 60% more E85 vs E10 gasoline for engine to run correctly. Simply don't use E15 use E10 or lower.
Instructor
Joined: Sep 2020
Posts: 101
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2023 C5 of the Year Finalist - Unmodified
Can we get a simpler answer on this deep dive? I have a stock 1995 LT1 six speed. Can I run the readily available 93 octane premium from shell that is up to E10 or do I keep making my 40 minute border cruise to get ethanol free 91 octane over the WI line? Car gets driven weekly or more in the summer but can sit about 2 weeks between garage idling in the winter. Last C4 was a 93 and only did ethanol free in it year round.
Team Owner
Joined: Jul 2004
Posts: 28,465
Likes: 3,288
From: Hartford WI
Can we get a simpler answer on this deep dive? I have a stock 1995 LT1 six speed. Can I run the readily available 93 octane premium from shell that is up to E10 or do I keep making my 40 minute border cruise to get ethanol free 91 octane over the WI line? Car gets driven weekly or more in the summer but can sit about 2 weeks between garage idling in the winter. Last C4 was a 93 and only did ethanol free in it year round.
Last edited by aklim; Mar 30, 2021 at 01:20 AM.
Drifting
Joined: Apr 2020
Posts: 1,925
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From: Orange, CA
Can we get a simpler answer on this deep dive? I have a stock 1995 LT1 six speed. Can I run the readily available 93 octane premium from shell that is up to E10 or do I keep making my 40 minute border cruise to get ethanol free 91 octane over the WI line? Car gets driven weekly or more in the summer but can sit about 2 weeks between garage idling in the winter. Last C4 was a 93 and only did ethanol free in it year round.