E85

[LanceD]

Trying out this corn fuel stuff. I've heard good and bad about it. I'll post my results here.
87 octane 16 mpg.
Filled up with E85 at $2.09gal with about an eighth of a tank of 87 left. It's about 2 miles out of my way going to work. Regular 87 was $2.49gal.

 

[Doubeleive]

probably nice if it is available locally to you, closest e85 to me is almost 60 miles away

 

[swathdiver]

Can you check your alcohol content Lance? My truck loves it and makes it run like race gas is in it. Have had instant economy lows in the 8s and highs in the 14s. Last 4 or 5 tanks averaged just over 10 mpg city driving. The GMT900 SUVs with 5.3s were rated between 10 city and 15 highway on E85.

 

[randeez]

prob a little late now...but make sure your truck is flex fuel compatible ...and mpg prob isnt the best comparison to gauge e85

if youve got a light foot and/or do a lot of highway mileage youll prob break even compared to 87oct.
with the stock tune i only ran 93oct, the e85 would keep up with it for highway mpgs and on cruise control climbing grades it would do better. going from 87 to e85 in performance though will prob rock but counterproductive to trying to save money

 

[LanceD]

How do I check alcohol content?

I am not real concerned about mpg, I just want it to run better and have better miles per dollar instead of miles per gallon.

 

[swathdiver]

It all boils down to how much does it cost to drive a mile. I've paid as little as .16 cents a mile and as much as .24 cents on E85 and up to .27 cents on 93 and that's with that pesky cat that's going to get replaced soon. My rig weighs at least 6,300 pounds and often much more, you fellas should do much better, especially the SWB trucks.


You need a scan tool which can read them. When the engine detects a refueling event, it takes seven miles of driving afterwards for the computer to calculate the new alcohol content. E85s alcohol content can vary greatly. I've gotten from 52-71% which I would think affect economy. Trying to use the same brand and stations, the last two tanks have been the highest from the same station. But they keep raising the price so I may jump ship and try the Sunoco across the street which is near thirty cents less per gallon.

 

[JonnyTahoe]

prob a little late now...but make sure your truck is flex fuel compatible ...and mpg prob isnt the best comparison to gauge e85

if youve got a light foot and/or do a lot of highway mileage youll prob break even compared to 87oct.
with the stock tune i only ran 93oct, the e85 would keep up with it for highway mpgs and on cruise control climbing grades it would do better. going from 87 to e85 in performance though will prob rock but counterproductive to trying to save money

 

[randeez]

you need a good deal more E85 to make the same power, IIRC the smaller (350cu in) injectors would only flow enough for about 300hp on pump gas. havent kept up with tbi injection since the age of e85 coming along, but i imagine they would support 25-30% less... swapping to the 454 injectors would probably be bare minimum necessary to keep hp up. I dont think i ever owned a truck that idled smoother than one with tbi injection not sure theres a way to "trick" the old pcm to run with a flex fuel tune, you'd either need to run it all the time or be able to switch between tunes.

i think if you do nothing but swap in the 454 injectors it would run rich as hell, duty cycle would still be commanding 350 sized injectors. without a tune it would probably run better with the larger injectors and straight e85

 

[Tkrysl]

Out of curiosity, what makes a vehicle E85 compatible? Will E85 really screw up my 2001 Burb?

I know very little about it.

 

[Scottydoggs]

it needs to be a flex fuel set up to run e85, or you need larger injectors and a tune to swap it over to run full time on e85.

i know a guy who got a content sensor set up so you can make it flex fuel. like a factory set up. dont know a much about other then he got it from http://getoverkilled.ca/products.html

 

[randeez]

The gmt800 flex fuel vehicles use a very expensive sensor, $400+ iirc....the tables may be in the non flex fuel vehicles just not enable. Some of those engines came with rediculously small injectors 24lb/28lb injectors will not flow enough e85 to keep up.

For gmt900 the factory uses a virtual sensor, which is just the o2 sensors monitoring outgoing exhaust and fuel trims to determine E-content, it's not that great.
Gmt900 the sensor is pretty cheap 50-75 depending on which you get, however you need some fittings to put it in the fuel line. I grabbed a sensor and quick disconnect fitting but it's to long to all go inline, so I need to grab some more plumbing to make it work. This probably what I'll end up buying:
https://dsxtuning.com/collections/f...sx-flex-fuel-kit-for-2006-2009-trailblazer-ss
Is gives you a y-adapter for power and you need to install a pin in the ecm

And @LanceD how'd your e85 adventure go?

 

[LanceD]

It's not that noticeable. Maybe a tad better? I will be filling up again soon and we'll see if it is worth the trip or not.

I do plan on a cam, dod and vvt delete, do you think with tuning it will make more of a difference?

 

[Etraeger]

Can't find the E85 in California very easily. I've seen it ONCE in my life in Southern California (I live in Central California). Scarcer than a Jackelope!

 

[JonnyTahoe]

Can't find the E85 in California very easily. I've seen it ONCE in my life in Southern California (I live in Central California). Scarcer than a Jackelope!

It's made from corn so it's more available in the Midwest. It's available at most gas stations but you really do not see many people using it. We also have E15 and E30 at a few stations. Our regular fuel has 10 percent ethanol mixed in during the winter months and some stations discount the mixed regular a bit so more people will use it.

 

[randeez]

It's not that noticeable. Maybe a tad better? I will be filling up again soon and we'll see if it is worth the trip or not.

I do plan on a cam, dod and vvt delete, do you think with tuning it will make more of a difference?

Tuning specifically for it will make a difference, when I was trying to find someone to tune mine a couple of them kinda gave me the "you might get another 15-20hp out of it, not really worth it" and most will just copy over the high octane tables and call it good. Im not to worried about dyno numbers, down here ambient temp is 90+degrees half the year...heat soak makes everything feel sluggish, only run 93 otherwise but even then it feels down on power. E85 isn't nearly as effected, knock is pretty much non existant in an NA engine with e85
Down here, E85 from the pump also ranges from a minimum of 50% ethanol to 85%, I haven't found a pump with over about e65 for the last few months. This is the downside of running it if you want max performance on it you may not be able to find any with a high ethanol content.
In theory it should meet whatever standards are set to call it e85 but I imagine whatever isn't ethanol is just crap low octane filler

 

[LanceD]

Fill up #2
292.8 miles @ 21.4 gallons.
Still $2.09/gal but 86 is down to $2.34
13.7 MPG on E85
16MPG On 86

 

[swathdiver]

They both equal .15 cents a mile at those prices and mpgs. Pretty cool eh?

 

[LanceD]

They both equal .15 cents a mile at those prices and mpgs. Pretty cool eh?

I dig it

 

[JonnyTahoe]

E 85 can be as much as 100 Octane. Older cars with carburetors can jet them to run on E 85 and it makes good power as it's around 100 octane.

 

[swathdiver]

That's what my truck feels like when using it, sure beats $10 a gallon for race gas!

I'm about to reset my fuel trims and to do so the alcohol content must be less then 10%, so back to 93 for two tanks while I do that and replace the cats.