250 miles round trip and it's the first time I've gotten all interstate since going E85 over a month ago. 17.4 average with mixed driving since the switch, but I got 19.4 interstate MPG, same E85 pump, speedo verified with GPS (63 MPH average with the short in town/entrance ramps/etc).

Specs: 5500 pound SSS, stock 6.0 LQ9 longblock, 4.10's, OBX LT's, stock cat back, Yank TT3000 restalled to 3200, Goodfella's "Boss" trans, AWD, 295/45/20's on Centerline Rapids, ported TB, SLP 1.85 rockers, custom CAI and HPT by me.

I want to get a lower stat and get some higher compression small port heads (keep velocity up) on there with a mild cam and see what she'll get!!!

 

6.0 + 4.10's Not bad!

 

So what kinda changes did you make to your tune to support the E85? How much did you increase the timing and what not?

 

Im running e85 and on this tank I think its going to be good. As of now it looks like im getting the same milage on e85 as I did on gas running 50-60mph trips.

Im using the stock timing table with the ethanol spark adder from a flex fuel tune. I don't no if the timing is making the diffrence or if im just thinking im going to get good milage.

 

I multiplied the injector sizing table by .7 (decrease of 30%) and that's IT!!! Spark table I added 2-3 on high timing table and 1-3 more on cruise cells. Same way I adjusted for a 93 octane tune. I just got my 42# injectors because I go lean (116% duty cycle) at 4500 RPM, so I've not gone full throttle in quite a while... which I would have done anyway since gas is so freaking expensive.

 

Are you reading the dash for your interstate mpg?

It will read incorrectly when you modify the tune like that.

Anyways, congrats on the conversion.

I am running a similar E85 tune right now and seeing similar #s on the dash.
Actual per tank average is around 16.5mpg

 

Actual 19.4, DIC indicated 19.1, same pump. I keep a small notebook in the glove compartment and write down each tank miles/gallons as well as oil changes. I'm a bit **** that way...

 

Nice #s man.

Corn is cool

 

Wish I could get that kind a mileage out of my truck I ran 4 tanks of E-85 though mine for the experiment and got right around 10.3-10.6 out of all of them . Now that I'm back to gas, I filled up yesterday and only got 13.1 Best I ever got out of my truck was a trip I took one time and got 18.5. Used to average 15-16, so don't know what the deal is. Maybe the 4.8 doesn't like 60lbs/hr injectors, Got a new surprise happening in about a week or so, so will see if that helps mileage any

 

Mileage might drop with a lower thermostat.

peace
Hog