E85...any reason Not to use it?

[swathdiver]

@swathdiver - while searching for a source for E30 fuel I stumbled across this post echoing what you said about E30, thought you might find it interesting.

https://www.greenhybrid.com/forums/f78/how-blend-your-own-fuel-why-you-should-16411/

Good post, thanks! Now you can download apps that tell you how many of each to pump to arrive at a certain alcohol percentage.

My truck has a BlackBear tune but still runs stock E85 tables. I would love to see the performance and mileage increase of this engine with an "ethanol tune".

If these Gen IV motors made just 5 to 6 more horsepower per cylinder, then AFMs duty cycle would increase to at least 50% and mileage would go way up like the Gen V Direct Injection LT motors.

 

[gooffeyguy]

Good post, thanks! Now you can download apps that tell you how many of each to pump to arrive at a certain alcohol percentage.

My truck has a BlackBear tune but still runs stock E85 tables. I would love to see the performance and mileage increase of this engine with an "ethanol tune".

If these Gen IV motors made just 5 to 6 more horsepower per cylinder, then AFMs duty cycle would increase to at least 50% and mileage would go way up like the Gen V Direct Injection LT motors.

It'd be nice for an app to also calculate the octane rating of the blended fuels

2001 Yukon SLT
2012 Yukon Denali XL
2011 Yukon Denali RIP 5/20/18

 

[Fless]

My truck has a BlackBear tune but still runs stock E85 tables. I would love to see the performance and mileage increase of this engine with an "ethanol tune".

@swathdiver, wouldn't a stock table be E10? I'm confused. What would be the difference between an E85 table and an ethanol tune?

 

[BG1988]

Less stuttering(knock) from the AFM when using 91 octane and above...
that is the whole point of using 91/93 octane or better (or e85)

 

[HiHoeSilver]

@swathdiver, wouldn't a stock table be E10? I'm confused. What would be the difference between an E85 table and an ethanol tune?

The flex truck has two tables. One for gas and one for ethanol. When he runs ethanol, the truck goes to the stock ethanol table and the tune is only commanding the TCM. A tune specifically for ethanol would alter that table the way his current tune altered the gasoline table.

 

[swathdiver]

It'd be nice for an app to also calculate the octane rating of the blended fuels

I think there is one that costs a few bucks. I've been working on one in an excel spreadsheet.

 

[gooffeyguy]

I think there is one that costs a few bucks. I've been working on one in an excel spreadsheet.

Well just playing around with a couple different calculators I've figured a 50/50 mix of 87 octane and E85 will give an octane of 96. A 50/50 mix of 93 octane and E85 will give 99 octane.

A 50/50 mix of non-ethanol fuel and E85 will give you a mix of E30 - E40 depending on the alcohol content of the E85 (usually 60 - 80%, at least around here, never seen anything over 75% with E85).

2001 Yukon SLT
2012 Yukon Denali XL
2011 Yukon Denali RIP 5/20/18

 

[Fless]

The flex truck has two tables. One for gas and one for ethanol. When he runs ethanol, the truck goes to the stock ethanol table and the tune is only commanding the TCM. A tune specifically for ethanol would alter that table the way his current tune altered the gasoline table.

Ahhh! I get it now. Obviously mine does the same thing.

 

[derfman00]

Gas Buddy is showing lowest 87 @ $2.00 per gallon with average about $2.20 across the area.

Same app shows E85 @ $1.87 for the lowest, some at $1.98 and most around $2.09.

I bet if you mixed 87 and E85 to get around 20% alcohol content you'd get better mileage and performance and save a little to boot.

That is the plan! I'm about 30 miles away from that 1.87 but live real close to the $2.09. The price dropped from when I made my post.

 

[fastscirocco]

If you have a 31 gallon tank and wait for the light, pump in 6 gallons of E85 and 20 of gasoline. If you're starting out with a higher alcohol content you can get the R+M octane rating up to 96 with these mixes.

I live in Michigan, come winter E85 can drop as low as 61% ethanol. I've read about using E85 test kits (glass vial) is there an easier way to confirm the ethanol percentage?
Is there a website that lists when the E85 has the ethanol percentage lowered?