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Anyone opinions using E85 for Track Days?

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You could have your tune are for a lower ethanol content, say E70. Will still get most of the benefit of E85 and not have to worry.
Yeah I guess that's an option. What would be the difference in HP between a 100 octane race tune and 70/85 ethanol tune?? My tuner said it was only about 10HP from 93 to 100 so I am even wondering why I run the 100.
 
Yeah I guess that's an option. What would be the difference in HP between a 100 octane race tune and 70/85 ethanol tune?? My tuner said it was only about 10HP from 93 to 100 so I am even wondering why I run the 100.
For you or anyone that is new to capless fuel systems and might transport E85 or other select fuel. Here's my funny story at my expense.

I have old school fuel cans with the kind of nozzle that slides in and out of the can. Those EPA nozzles are no fun. The old nozzles are pretty narrow and a bit flimsy but work perfectly fine with a 2008 and 2011 Jeep. I maximize my fuel discounts by also fulling up cans.

When I when to pick up the mustang I figured I'll throw a can in the Jeep then fill with E85 and put in the mustang just in case my milage estimates were off or if I decided to stretch to the next gas station on the way home. I can here a few of you laughing right now because you know where this is going...
Well, I decided to run low and dump the 5 gal in at a rest area and ended up in a bit of a crapper. The nozzle diameter was too small and would not open the flap. I few minutes later I come up with a MacGyver solution. I wrapped it with a cigarette pack and it works. Ok - fuel in good to go right? Wrong - everything tightened up and the flap partially closed and couldn't get the cardboard and nozzle out. Pretty good ahh chit moment. I little more creativity with a couple small screw drivers and it comes out.

Moral of my story- There is a fuel funnel in the trunk with the spare....
 

Fabman

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For you or anyone that is new to capless fuel systems and might transport E85 or other select fuel. Here's my funny story at my expense.

I have old school fuel cans with the kind of nozzle that slides in and out of the can. Those EPA nozzles are no fun. The old nozzles are pretty narrow and a bit flimsy but work perfectly fine with a 2008 and 2011 Jeep. I maximize my fuel discounts by also fulling up cans.

When I when to pick up the mustang I figured I'll throw a can in the Jeep then fill with E85 and put in the mustang just in case my milage estimates were off or if I decided to stretch to the next gas station on the way home. I can here a few of you laughing right now because you know where this is going...
Well, I decided to run low and dump the 5 gal in at a rest area and ended up in a bit of a crapper. The nozzle diameter was too small and would not open the flap. I few minutes later I come up with a MacGyver solution. I wrapped it with a cigarette pack and it works. Ok - fuel in good to go right? Wrong - everything tightened up and the flap partially closed and couldn't get the cardboard and nozzle out. Pretty good ahh chit moment. I little more creativity with a couple small screw drivers and it comes out.

Moral of my story- There is a fuel funnel in the trunk with the spare....
A transmission fluid funnel works slick.
 
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I found that any stiff funnel tip works. Sometimes you have to jam it through a few times with some force and you get it right and it opens. If you use a size closest to the Ford freebie that came with the car the effort is less. So there is something about stiffness and diameter that makes the capless open
 
I found that any stiff funnel tip works. Sometimes you have to jam it through a few times with some force and you get it right and it opens. If you use a size closest to the Ford freebie that came with the car the effort is less. So there is something about stiffness and diameter that makes the capless open
Yes. There's are 2 releases, right and left, that have to be depressed to allow the flap to open.KIMG3834.JPG
 
Here's a cool power point from IQ Learning Systems. If you hover over the title below you can open the hotlink strait to the power point.

"E85 The Next Street Performance and Racing Fuel"

Here's their formula for calculating ETOH percentage. It was a little confusing for me at first. The numbers 2.1 and 1.94 are constants that never change if you use a 100cc cylinder. The numbers that can change are the ones in the parenthesis -Volume A and B. The 13.58 in the formula is the result of the difference of A and B multiplied by the constant 1.94

E85 Test.png
There are the cheapest cylinders I can find but no stoppers.

https://rover.ebay.com/rover/1/711-...0001&campid=5338634152&icep_item=324201469220

https://rover.ebay.com/rover/1/711-...0001&campid=5338634152&icep_item=352585006179

Or Rev-X has these for 13 bucks and no math.

https://rover.ebay.com/rover/1/711-...0001&campid=5338634152&icep_item=263692795283

https://rover.ebay.com/rover/1/711-...0001&campid=5338634152&icep_item=264160078584

There's other testers out there also...
 
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Let me give you guys a heads up about Ethanol and fire suppression. I did a huge study for our city because we host an Indycar race there and I was charged with dealing with incidents on the wall side of pit row. E85 does not go out easily, nor does the Indy spec E98. There's enough gasoline in there to get it to light and once that burns off, the flames are basically invisible, you have to look for the heat trace to see where the fire is at (although watching something degrade while being consumed in an ethanol fire is kind of cool because, except for the smoke emitted by the thing burning, it just kind of disappears) Things like Cold Fire and other products grouped under "emulsifiers" that are designed to mix with the fuel also don't work very well, yes I know Indycar and the NHRA uses them, but they don't work very well on ethanol fires. What DOES work, reasonably well is ARAFFF (alcohol resistant aqueous film forming foam) you used to be able to scrounge this from your local fire department after training events, but some of it's contents have now been listed as a possible carcinogen, so good luck with that. I have a stash of in my garage. Go find a water extinguisher, fill it with water as designed but short it by about a quart, add your ARAFFF to it, and pressurize it, you're done, You have an extinguisher that will put out gasoline, rubber, alcohol and common combustibles (but not energized electrical equipment). It doesn't leave very much residue like a dry chem that will etch everything it touches and it can be filled at your home. (some have a valve core in them, others you can back fill through the nozzle by opening the valve ) Barring that, you can use an emulsifier, but don't expect results much better than water only.
I keep several of these around the garage and especially when I'm welding.

uN7GFdll.jpg
 
I sucked it up and paid the 13 bucks for the multi line tester just in case I wanted to test what was going in my outdoor power equipment. ETOH is the #1 killer of small engine fuel lines and carburetor diaphragms. Also, I thought doing the math would take the fun out of it and know I've spent more money on less useful things.

Winter blend potentially confirmed at a Pittsburgh Speedway. I have a feeling that it might be their regular blend though because I never see anyone at that pump. When I get a retune I'm going to make sure that it's a conservative one. From reading 74 ish percent from a regular pump is super. The pump actually states that it could range from 50-85. If I conservatively rate the ETOH at 112 in a 112-115 scale and use the filler as 87 that still puts the octane rating at hypothetical 106 at completely optimal tune and conditions. I have to admit that cheated with this online calculator http://www.wallaceracing.com/ethanol-mix-calc.php and just scaled it up substituted 74 gal of 112 ETOH and 26 gal of 87 = E74. The calculator puts E85 at 108 but many places rate E85 at 100-105. Even so, E74 will have more octane than any regular pump gas even if it ends up 98-102 that's pretty good. Any chemists in TMO? Have a quiet and safe Sunday!
KIMG3846.JPG
 
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Fabman

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I sucked it up and paid the 13 bucks for the multi line tester just in case I wanted to test what was going in my outdoor power equipment. ETOH is the #1 killer of small engine fuel lines and carburetor diaphragms. Also, I thought doing the math would take the fun out of it and know I've spent more money on less useful things.

Winter blend potentially confirmed at a Pittsburgh Speedway. I have a feeling that it might be their regular blend though because I never see anyone at that pump. When I get a retune I'm going to make sure that it's a conservative one. From reading 74 ish percent from a regular pump is super. The pump actually states that it could range from 50-85. If I conservatively rate the ETOH at 112 in a 112-115 scale and use the filler as 87 that still puts the octane rating at hypothetical 106 at completely optimal tune and conditions. I have to admit that cheated with this online calculator http://www.wallaceracing.com/ethanol-mix-calc.php and just scaled it up substituted 74 gal of 112 ETOH and 26 gal of 87 = E74. The calculator puts E85 at 108 but many places rate E85 at 100-105. Even so, E74 will have more octane than any regular pump gas even if it ends up 98-102 that's pretty good. Any chemists in TMO? Have a quiet and safe Sunday!
View attachment 61040
This is pretty cool, where did you get this?
 
This is pretty cool, where did you get this?
They have 2 but one only goes from 65-100. I liked the one with zero to 100 measurments. I checked the voulme of water and fuel - 59cc and 91cc. If someone wants to make one all you have to do is get a 150mm/5 oz bottle put the 59cc in make a mark top off with the other 91cc make a mark then do 19 evenly spaced marks for each 5%. The bottle are not cheap though- plus the time.

REV-X E85 Super Tester Ethanol Test Bottle - Tests E0% - E100% - Easy to Use Kit
 
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Fabman

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They have 2 but one only goes from 65-100. I liked the one with zero to 100 measurments. I checked the voulme of water and fuel - 59cc and 91cc. If someone wants to make one all you have to do is get a 150mm/5 oz bottle put the 59cc in make a mark top off with the other 91cc make a mark then do 19 evenly spaced marks for each 5%. The bottle are not cheap though- plus the time.

REV-X E85 Super Tester Ethanol Test Bottle - Tests E0% - E100% - Easy to Use Kit
I have something similar, but yours is way cooler.
 

Fabman

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I still have a sealed drum of e85 left over from the beginning of the 2019 season....I wonder if it still usable?
I have heard that 2 years was about the limit but not sure how accurate that is.
Anybody know for sure?
 
I still have a sealed drum of e85 left over from the beginning of the 2019 season....I wonder if it still usable?
I have heard that 2 years was about the limit but not sure how accurate that is.
Anybody know for sure?
I have no Idea but have seen guys on other forums say the have done nothing with the fuel in their car through the winter with no problems. My thoughts- If the drum is sealed can it actually be oxidized? Only the gasoline side will degrade. How many years/decades does wiskey last unopened ? Same alcohol ( Ethanol, ethyl alcohol, ETOH). Just to be safe I would contact a supplier that sells drums and see if you can get an honest answer.
 
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I still have a sealed drum of e85 left over from the beginning of the 2019 season....I wonder if it still usable?
I have heard that 2 years was about the limit but not sure how accurate that is.
Anybody know for sure?
Hoping somebody chimes in with a definitive answer. I'm wondering the same thing about 3 5gal. pails of X85 from 2019
 

Fabman

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DC4677F3-B1AA-49DF-A1EA-40BB57A0E0C9.jpeg
 

PaddyPrix

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Hoping somebody chimes in with a definitive answer. I'm wondering the same thing about 3 5gal. pails of X85 from 2019
I can take it off your hands if not :)

Although, perhaps X85 is a touch too fancy for my Tahoe flex tow rig.
 
So, if you habe a flex-fuel tune, at what point (if any) do the lower ethanol E85 mixes perform worse than good old pump 93 octane? Say I can only find a 60% E85 blend....is it better to just use 93 instead?
 

Fabman

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So, if you habe a flex-fuel tune, at what point (if any) do the lower ethanol E85 mixes perform worse than good old pump 93 octane? Say I can only find a 60% E85 blend....is it better to just use 93 instead?
I’ve run it all the way down to the mid 70’s it’s always better than gas.
 

Fabman

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So, if you habe a flex-fuel tune, at what point (if any) do the lower ethanol E85 mixes perform worse than good old pump 93 octane? Say I can only find a 60% E85 blend....is it better to just use 93 instead?
Any amount of Ethanol is better than no Ethanol when it comes to knock prevention, the problem area is that unless you have a flex tune the tune needs to be changed for radically different mixes. My race tunes were the same as my street tunes (different boost numbers/different timing) and they were open loop tunes, so no flex about it, still I was fine in the 70's on 20 psi. Remember, when ethanol content goes down, the mixture richens up....so it wont burn down, its just gets too fat. Too Rich is safer than too lean. As for flex tunes, my 2011 F 150 had a flex fuel Coyote in it and it would run any ethanol content from 0% to 99%. Your tune may vary. LOL.
 

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