Iowa has a decal on all E85 pumps that states it will be no lower than 70% ethanol.
Why is e85 still for sale everywhere?
- Thread starter Klutch9
- Start date
No pump E85 is 85%, by definition E85 is 51-83% maximum. Some chains do advertise a minimum of 70% ethanol at the pump, but most are a crapshoot as to their actual percentage.
Now, “race” E85s from blenders like Rockett, VP, Ignite, etc are true 85% ethanol and are usually mixed with oxygenated race fuels as well and can end up in the 110-115 octane range. These fuels are a far cry from what’s available at your typical station’s E85. Part of the increased power is due to being able to add additional timing to take advantage of the knock resistance, but the real power boost comes from the much higher latent heat of vaporization of ethanol, which results in a large drop in temperature in the incoming air/fuel charge, which increases its density, and therefore the engine is able to ingest and burn more air/ethanol than air/gasoline.
Pump E85 cannot be classified as “cheap race gas” because of its highly variable quality, but it can be used to make additional power due to the cooling effect of ethanol. But unless said engine had high enough compression that a significant amount of timing had to be pulled from optimal, there is not going to be an earth-shaking increase from octane alone. Octane doesn’t make any power if it’s not needed to prevent detonation.
Nah, even crappy e85 makes more power on NA engines that are tuned and jetted to use it because it’s oxygenated allowing more fuel to burn with the same amount of air.
More btus burned per stroke is more power, that’s outside the effects of compression
You’re not comparing apples to apples and ignored the unarguable fact that increased octane does not in itself increase power, especially when the ignition timing is not limited by the dynamic compression ratio of the engine.
“Tuned & jetted to use it” is not apples to apples. Again, it goes back to the cooling effect of ethanol vaporization which increases the density of the intake charge (more oxygen is contained in the charge when it is cooler, which requires additional fuel to maintain the correct AFR). This is how a stock flex-fuel engine makes 8-10 or so HP more on E85. The downside is it takes more fuel to supply that BTU amount, so mileage suffers.
On a stock NA engine, flex fuel/E85 is a scam, where the only beneficiaries are farmers selling corn for ethanol at subsidized prices for dubious environmental benefits. Nothing like paying people to use a less environmentally-friendly fuel that results in worse mileage for daily drivers…
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e85 requires less oxygen per btu to burn because the fuel already includes 02 in it’s chemistry.
In a naturally aspirated engine that allows for more power, this has nothing to do with octane or cooling by itself.
My highschool had a simple low compression test engine that we could randomly adjust AFR, fuel, timing and spark intensity for monitoring and run random fuels.
Methanol > Ethanol > Gasoline
I saw it and measured myself , I don’t require subjection. Cooling differences are minimal between ethanol and methanol yet methanol can make the most power because it requires the least air per btu to ignite. It’s simple chemistry.
Sure it’s not double but for just adding more time, spark and fuel the increase in power was measurable even if the fuel consumption to do so was massively more.
The cooling affect is icing for someone towing or running hard.
In a naturally aspirated engine that allows for more power, this has nothing to do with octane or cooling by itself.
My highschool had a simple low compression test engine that we could randomly adjust AFR, fuel, timing and spark intensity for monitoring and run random fuels.
Methanol > Ethanol > Gasoline
I saw it and measured myself , I don’t require subjection. Cooling differences are minimal between ethanol and methanol yet methanol can make the most power because it requires the least air per btu to ignite. It’s simple chemistry.
Sure it’s not double but for just adding more time, spark and fuel the increase in power was measurable even if the fuel consumption to do so was massively more.
The cooling affect is icing for someone towing or running hard.
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Race cars
Not to split hairs but it certainly is.
Harris Teeter here has tested E90 for me once and E83(ish) once. The other station in town who sells it (Marathon) has always tested E80 for me.
My data sample is only about half a dozen tests but I've never bought E85 from a local pump that tested lower than E80.
NEX at NOB still has it and the Harris Teeter on Granby street has it. I've bought from both places a half dozen times in the last 6 months. The NEX tested E80 both times and the Harris Teeter has always been between E80 and E90. It doesn't seem to change around here for Winter, seems to be no "Winter blend" here.
Then it doesn't meet the requirements for E85 and is falsely labeled for sale as E85. So, either Harris Teeter is selling fuel that doesn't meet specifications, or your tester is somehow incorrect. My statement about no pump E85 not being 85% is based on ASTM standards:
ASTM D5798-21 said:
Notice it doesn't say 85%, or above that. It's a specification requirement, not a recommendation, to be between 51 & 83%. You're lucky that your local pumps have 80% content, but there's nothing requiring them to have that high of a percentage on a regular basis. Also, as a saavy consumer, you should be appropriately adjusting your price targets based on ethanol content- fuel that is consistently 80% ethanol should be priced lower than fuel containing only 60% ethanol, or else one is giving their money away to the fuel company.
U.S. Department of Energy said:
https://afdc.energy.gov/fuels/ethanol-e85-specs
Worth noting in the early days of e85 where it would get dumped into a vintage gas tank it was very common to have e90 as a tiny bit of water would draw the ethanol out into the pickup. As you ran the tank down past halfway your ethanol content would drop off.
The Sheetz stations have a pump that is labeled "flex fuel", and everyone understands that can be anything from 51-83% because the pump says that right on it, but then there are other pumps that say "E85"...they don't say flex fuel like the Sheetz pumps do.
I'm not on FB, but there is a local FB group that is for E85 users and everyone posts their E content test results from a particular station so others know where to go.
I own both a flex fuel (Tundra) and a plug-in hybrid (new Volvo XC90). I don’t know what the energy future looks like, because it varies so much with administrations, but I have most of the bets covered.
Unfortunately, your old mount that guzzled JP5 like a North Carolinian on a moonshine delivery run (1950s NASCAR qualifier?
) is only still fielded by a non-friendly place.Most of us are obviously gun-shy with the amount of federal spending these days, but I for one would be behind a new fighter design based on a movable-wing aircraft. But it's gotta do the original justice
I've talked to a few Subaru wrx STI owners that claim with a few mods it makes for great power and you can run additional boost.
I filled up again today with E85 in the mommy missile. It seemed to do ok on the last tank. Yes MPG dropped but not by the 34% cost savings by my math. To be fair I’ll need to run a few more tanks.
I also intend to test this E85 to see what the ethanol content is.
I also intend to test this E85 to see what the ethanol content is.
My 96 Mercury Grand Marquis loves premium fuel even though it was originally designed for regular. 263,000 miles have probably changed the engine over time and fuel is probably different than back in 96. I have found mixing as much as 50/50 E85 and regular produce a higher octane blend that my old GM loves. Noticeable power increase and no knocking on steep hill climbs that happens with regular until it downshifts. I do tend to lose around 10% fuel economy so if price is the factor I only need to beat the price by 10% which is usually easy. However in my case performance is also a factor and have been using this fuel blend for the last 150,000 miles without harm. I have noticed if I put more E85 than 50% the car begins to stutter feels like a slight misfire and pedal becomes light feeling.
When I moved to IA and got my company Chevy with the 8.1L, I assumed it was E85 and filled it up. It was winter. It would start very hard, and then lope like a top fuel dragster for a minute or so until it warmed up enough for a smooth idle. Sounded awesome.
Oddly enough it never threw a CEL, but I only ran a couple tanks before I figured out it was not E85 compatible.
The first generation Ford flex fuel cars were very hard to start in the winter but it’s worth noting that e85 pumps didn’t use to reduce ethanol content in the winter months either.
interesting discussion, here in NE Pa Sheetz is the only flex fuel i ever seen, they also have no eath i use in my carbed small equipment. corn which is almost all GMO + products made from it is not fit for humans unless your a fan of AGENT ORANGE!! theres a formula on line about mix ratios + optimizing your engine for high eathanol is needed to get the most value from using it, lots of varying info for sure!!!
