I'm just not exactly sure if I can just do a 75/25 mix of e85 or if I need a retune for it. I know whipple says use 93 octane but 91 will do.

 

I think the gas tank is about 21-22 gallons, so Ill try 5 gallons e85 and the other 16-17 gallons will be 91. This should maybe bring me up to like 94-95 octane?

 

Not sure if it works that way and mixes....

You can add 2 gallons of toluene and 14 gallons of 93 and that will give you a 95 octane tankful. Add 4 oz of marvel mystery oil for each gallon of Toluene.

 

After work I'll fill up with 5 gal e85 and the rest 91 and see how it works. AZ already uses Ethonal mixtures but I'll see if it runs any leaner on the wideband. Truck right now is overly rich with whipple tune. WOT is 10 flat on wideband probably worse.

 

Kind of a no brainer eh? 91 Octane vs 105........ Unfortunately E85 is not readily available here in the Great White North and it is more expensive than unleaded. And the Arseholes that sell it will not sell it to you in a Jerry can nor a non E85 vehicle.

 

The extra hp is crazy but it is my daily driver and as Fatherford stated efficiency drastically decreases. But at $3++ for 93 octane here in Houston the cost/mpg of the two different octanes may be worth the switch if they balance each other some, plus the extra 50hp of course!

 

On my Roush set up it has a sticker on the inside of the gas door that specifically says not to run e-85. Thats all I know for what thats worth.

 

In NA form the trucks can run on either. Once SC'd it would have to be tuned to run on one or the other.

 

I've heard if you truck isn't a flexfuel meaning run either or you can run e85?

 

Well I saw E-85 is selling for around 2.50, while supreme is near 3.20.. It almost evens out.

That is correct, unless you are tuned for E-85 on a blown truck you can not run it. You also will mostly like need 60# injectors and a dual fuel pump setup as e-85 requires roughly 30% more fuel.

That is halfway a myth...

Some claim that seals will rot away if you don't have an e-85 capable vehicle. That has been pretty much shot down time and time again. Pretty much any vehicle with a recent EFI system can run e-85 and the seals are fine.

The big factor is if the vehicle can "tune" itself for E-85, and unless you have a flex fuel vehicle it can't without proper aftermarket tuning. The second biggest factor is if your injectors/fuel pump can keep up.

Since I'm already running 60's and have a dual fuel pump kit, I'm good to go.

 

This is a 2011 5.0 mustang with a pro-charger and exhaust. The car did 670rwhp on 93 octane, then put out this new number on E-85...

 

Wow, that's impressive

 

Not really true. The official data says more like 97. Pure ethanol is about 104. The more ethanol in the fuel, the wider the spread is between research and motor octane numbers, and pump octane is the average of those 2 numbers.

 

Two clips from the SCT Pro Racer Support forum:

E85 is a 8-9 to one A/F so you will need to do some tuning on the MAF and increased timing due to higher octane rating of the E85 (approx 117)
I currently run E85 in a 99 Ford Lightning with a built tranny and engine, stock Eaton, 60lb Inj and BA2400 MAF, open headers, 4:10 gear. and another tune for 93 Octane gas. E85 for the strip and 93 for the roads.
Tune till your wide band reads 12.8 or 11.8 if blown/turbo, i added 11 deg of more timing on the blown Lightning.

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Even those of you running standard pump gasoline are probably getting a mild alcohol blend. By law, most gas stations today are now allowed to sell blends of as much as 10% ethanol as "gasoline". The ethanol is being used to displace the MTBE (methyl tert-butyl ether), which has its own environmental and health concerns. It used to be that stations were required to post a sticker on the pump declaring the alcohol content, but that's no longer happening. Some regions were quicker to adopt the maximum allowable ethanol content in the pump gasoline. In my travels and discussions with shop owners and calibrators across the country, I've found that almost every station can be assumed to be selling some alcohol blend unless stated otherwise. In most cases, this means assuming a blend of 10% ethanol. Any addition of alcohol blends to the gasoline will shift the stoichiometric balance point. The more oxygen carried by the fuel, the richer the stoichiometric point will be. Where E85 has a stoichiometric ratio of 9.85:1, E10 (most pump gas blends) will balance at about 14.2:1. This means that tuning to an assumed pure gasoline composition with a stoichiometric point of 14.64:1 may include a 3% error before the engine is ever started. The wideband oxygen sesor will still typically display "14.64:1" at lambda=1.00, even though this is really an actual ratio of 14.2:1 with a 10% ethanol blend. Three percent may not sound lick much, and it really isn't, but the idea behind engine calibration is to get all variables as close to optimal as possible. Leaving a 3% error in the fuel's stoichiometric point just makes tuning the volumetric efficiency table, startup fuel, and transient fueling that much less accurate. It's a good idea to just adjust at the beginning before baking that error into every other calculation later on.

 

You are correct, but the "equivalent" is around 105 or so due to the cooling properties etc.