About E85

[Dragsinger]

For those of you racing with E85, please tell me what you think of doing so. Also, if you have run with both E85 and Methanol, how do they differ? What are the pros and cons of each?

[swampbuggy]

Hello Larry, i will start the ball rolling by stating what i know about your questions. E-85 fuel is 85 percent ethanol alcohol and 15 percent ?? ethanol is produced from plant based products such as sugar and other items too. Methanol alcohol on the other hand is produced from products found within the earth such as natural gas, coal, and maybe some other items ?? . Both fuels require more fuel volume to the same amount of air than Gasoline. Both fuels are quite corrosive. Both fuels will keep an engine cooler under WOT conditions. Methanol will definitely produce more power when the correct F / A ratio is reached, how much more is some what argued. One stinks when exhausted ( ethanol ) , the other one smells good to most folks ( methanol ) . Mark. H.

[David Redszus]

Both methanol and ethanol will absorb water equal to their own weight. It is hard to find
dry methanol or ethanol.

Having tested hundreds of fuel samples for Formula SAE, I can assert that E85 does not contain 85% ethanol;
the content may vary from 70% to 87%, and the remaining component is an unknown, except for the water content.

As far as the base alcohols, here are some basic properties when used as a fuel.

Methanol
CH3OH
SpG 0.795 dry
Boiling point 149F
Stoich 6.47
Oxygen 49.9%
Flame temp 4873F
Heat of combustion 8589 BTU/lb
Energy 1328 BTU/lb air
Heat of vaporization 78.5 BTU/lb air

Ethanol
C2H5OH
SpG 0.794 dry
Boiling point 174F
Stoich 8.99
Flame temp 4911F
Oxygen 34.7%
Heat of combustion 11493 BTU/lb
Energy 1278 BTU/lb air
Heat of vaporization 41.2 BTU/lb air

While methanol does produce about 4% more energy (BTU per lb of air) than ethanol, it's major
advantage is it's charge cooling ability which is 90% greater than ethanol. Ethanol charge cooling
being about 4 times greater than gasoline.

[ProPower engines]

As David mentioned Methanol produces more power potential then E85 will.
The inconsistancies of E85 compared to packaged race methanol is dramatic. Its blended by the tanker load in small batchs but the formula is basicly add ethanol then some gas then the binder chemicals then truck to the station that sells it and mix with whats left in the tank.
If they do not sell lots by volume the vapor loss of the chemicals changes the % of gas or ethanol on hotter days compared to cooler.
E100 can be had by compared to getting fuel at the local the barrel and then ad the gasoline to suit your needs. You can vacuum seal a drum of E100 easily and is easier then getting the blended fuels at service stations and dealing with the different mix ratios.

With lots of testing you can make it work but race fuels just need to be the same from batch to batch to avoid engine isues

[Dragsinger]

Thanks for the feedback. I see no reason nor advantage to change from Methanol.

[JDR Performance]

We've worked with it for over 20 years and it has advantages and disadvantages. It'll produce more power than gas and less than methanol in most cases. Fuel system components need to be alcohol compatible if you want longevity. You have a lot less fuel consumption than with methanol, some cooling advantage over gas and an an increase in fuel consumption. Using it for a long time can leave a sticky deposit in the intake. Fuel blend at the pump can vary in ethanol content but you can be creative with the ethanol percentage and oftentimes mix down to a lower ethanol content if desired as long as you tune for it and keep it consistent. In our area we're fortunate to have a source for ethanol so it can be mixed as needed. Fuel from the pump here hasn't been bad here either and for $1.50 or whatever it is today it does well. Lambda and time slip readings don't show major issues with it as long as you keep the fuel blend consistent. It's available from VP, Renegade, and Sunoco for those that prefer to purchase it that way. It requires a little more effort than gas or methanol but it does work.

[Walter R. Malik]

Both methanol and ethanol will absorb water equal to their own weight. It is hard to find
dry methanol or ethanol.

Having tested hundreds of fuel samples for Formula SAE, I can assert that E85 does not contain 85% ethanol;
the content may vary from 70% to 87%, and the remaining component is an unknown, except for the water content.

As far as the base alcohols, here are some basic properties when used as a fuel.

Methanol
CH3OH
SpG 0.795 dry
Boiling point 149F
Stoich 6.47
Oxygen 49.9%
Flame temp 4873F
Heat of combustion 8589 BTU/lb
Energy 1328 BTU/lb air
Heat of vaporization 78.5 BTU/lb air

Ethanol
C2H5OH
SpG 0.794 dry
Boiling point 174F
Stoich 8.99
Flame temp 4911F
Oxygen 34.7%
Heat of combustion 11493 BTU/lb
Energy 1278 BTU/lb air
Heat of vaporization 41.2 BTU/lb air

While methanol does produce about 4% more energy (BTU per lb of air) than ethanol, it's major
advantage is it's charge cooling ability which is 90% greater than ethanol. Ethanol charge cooling
being about 4 times greater than gasoline.

The 15% of gasoline in E85 makes up any difference in energy output per pound.

That is ... as long as it is really E85 from a racing fuel manufacturer.
I have tested several batches from normal service stations throughout the year and it varies greatly from 67% Ethanol to 88% Ethanol from these tests. Pretty difficult to get a good tune with this much variation.

I might change to M5 though ...

[David Redszus]

Both methanol and ethanol will absorb water equal to their own weight. It is hard to find
dry methanol or ethanol.

Having tested hundreds of fuel samples for Formula SAE, I can assert that E85 does not contain 85% ethanol;
the content may vary from 70% to 87%, and the remaining component is an unknown, except for the water content.

As far as the base alcohols, here are some basic properties when used as a fuel.

Methanol
CH3OH
SpG 0.795 dry
Boiling point 149F
Stoich 6.47
Oxygen 49.9%
Flame temp 4873F
Heat of combustion 8589 BTU/lb
Energy 1328 BTU/lb air
Heat of vaporization 78.5 BTU/lb air

Ethanol
C2H5OH
SpG 0.794 dry
Boiling point 174F
Stoich 8.99
Flame temp 4911F
Oxygen 34.7%
Heat of combustion 11493 BTU/lb
Energy 1278 BTU/lb air
Heat of vaporization 41.2 BTU/lb air

While methanol does produce about 4% more energy (BTU per lb of air) than ethanol, it's major
advantage is it's charge cooling ability which is 90% greater than ethanol. Ethanol charge cooling
being about 4 times greater than gasoline.

The 15% of gasoline in E85 makes up any difference in energy output per pound.

That is ... as long as it is really E85 from a racing fuel manufacturer.
I have tested several batches from normal service stations throughout the year and it varies greatly from 67% Ethanol to 88% Ethanol from these tests. Pretty difficult to get a good tune with this much variation.

I might change to M5 though ...

The Heat of Combustion values are only part of the energy story. We must also consider the stoich value of each fuel component; that is the BTU/ lb of air burned.

The 15% gasoline added to ethanol does not make any difference in energy output since both have the same
BTU/lb air values.

And yes, the variances in E85 are considerable, both seasonally and from batch to batch. If any alcohol based fuel is
to be considered, the water test should be performed as well as SpG.

All that said, drummed race fuel from major refineries may also have consistency problems.
And fuels stored in plastic jugs are only good for lawn mowers.

[Walter R. Malik]

The 15% of gasoline in E85 makes up any difference in energy output per pound.

That is ... as long as it is really E85 from a racing fuel manufacturer.
I have tested several batches from normal service stations throughout the year and it varies greatly from 67% Ethanol to 88% Ethanol from these tests. Pretty difficult to get a good tune with this much variation.

I might change to M5 though ...

The Heat of Combustion values are only part of the energy story. We must also consider the stoich value of each fuel component; that is the BTU/ lb of air burned.

The 15% gasoline added to ethanol does not make any difference in energy output since both have the same
BTU/lb air values.

And yes, the variances in E85 are considerable, both seasonally and from batch to batch. If any alcohol based fuel is
to be considered, the water test should be performed as well as SpG.

All that said, drummed race fuel from major refineries may also have consistency problems.
And fuels stored in plastic jugs are only good for lawn mowers.

From what I can remember, though I may be mistaken ... true E85 has about 35% more energy per liter than Methanol & about 30% more MJ per Kg of liquid.

I don't think Methanol stoich is 30% higher than E85 but, maybe.

[David Redszus]

The 15% of gasoline in E85 makes up any difference in energy output per pound.

That is ... as long as it is really E85 from a racing fuel manufacturer.
I have tested several batches from normal service stations throughout the year and it varies greatly from 67% Ethanol to 88% Ethanol from these tests. Pretty difficult to get a good tune with this much variation.

I might change to M5 though ...

The Heat of Combustion values are only part of the energy story. We must also consider the stoich value of each fuel component; that is the BTU/ lb of air burned.

The 15% gasoline added to ethanol does not make any difference in energy output since both have the same
BTU/lb air values.

And yes, the variances in E85 are considerable, both seasonally and from batch to batch. If any alcohol based fuel is
to be considered, the water test should be performed as well as SpG.

All that said, drummed race fuel from major refineries may also have consistency problems.
And fuels stored in plastic jugs are only good for lawn mowers.

From what I can remember, though I may be mistaken ... true E85 has about 35% more energy per liter than Methanol & about 30% more MJ per Kg of liquid.

I don't think Methanol stoich is 30% higher than E85 but, maybe.

When based on fuel liquid (per pound), E85 has 34% more BTUs than methanol. But when the basis is energy per pound of air that can be burned, methanol comes out ahead by about 4%. 1328 vs 1276.

But these lab values are based on pre-mixed bomb calorimeters, and not on running engines with inlet charge cooling.

[PSA]

I haven't looked into it, but most efi can run ethanol sensors today. Maybe they are accurate enough to compensate for different ratios once a couple of verified blends have been used.

[F-BIRD'88]

I haven't looked into it, but most efi can run ethanol sensors today. Maybe they are accurate enough to compensate for different ratios once a couple of verified blends have been used.

Street E85 "flex fuel" OEM EFI vehicles are designed to adjust for what every mix you get at the pump. as it does vary.

[mt-engines]

For those of you racing with E85, please tell me what you think of doing so. Also, if you have run with both E85 and Methanol, how do they differ? What are the pros and cons of each?

The only difference I have seen is Methanol requires more preheat than E85. Otherwise both are great fuels. Only a few times I have ran into bad pump E85 that must have been mostly water, lost quite a few mph at the track.

But the price and availability of E85 around here makes it very appealing. I have built quite a few 14:1 compression "pump gas engines" for guys that like to cruise and have a hot street car. its an easy 30ftlbs vs premium pump

[Rick!]

https://www.enginelabs.com/engine-tech/ ... d-to-know/

Pretty sure no one is running 14:1 compression on the allowable E51 masquerading as E85.
At the same time, there probably isn't a winter blend of E85 in FLA...
My brother looked into this almost 10 years ago for his door car.
On the dyno, it had a little more torque and about the same HP.
Hearing about ethanol consistency, or rather inconsistency, is what kept him running race gas.

[PSA]

I haven't looked into it, but most efi can run ethanol sensors today. Maybe they are accurate enough to compensate for different ratios once a couple of verified blends have been used.

Street E85 "flex fuel" OEM EFI vehicles are designed to adjust for what every mix you get at the pump. as it does vary.

Yes, I'm just not sure how well an aftermarket ecu and sensor works for something more performance oriented. But I'm guessing it's straightforward tuning for everything but cold climate start up.