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Posted

Here;s some more proof for you E85 lovers, straight from my own window sticker. See the note on MPG for E85?

 

I do not disagree MPG is lower with E85, but Horsepower and Torque are higher on E85.

Posted

???? So you too are telling me E85 has more BTU's per gallon than gasoline? WTF is everyone smoking over here???

Posted

???? So you too are telling me E85 has more BTU's per gallon than gasoline? WTF is everyone smoking over here???

 

 

Are you illiterate? No one is debating that E85 has lower energy density.

  • Like 1
Posted

I don't see how it;s possible. If you raise compression & advance timing to the level required to make good power with E85, the computer would have to retard timing so much in order for the engine to live that it wouldn't make crap for power on unleaded.

 

Maybe this explains why with these trucks, E85 DOES have more power than regular ....

Posted

The engine runs richer and advances timing on E85 and leans out some and retards timing on regular. It can tell what you use.

Posted (edited)

Alright, well then that proves my point these engines ARE indeed optimized for E85, and NOT regular unleaded.

Edited by Jsdirt
Posted (edited)

No change in compression ratio. Bump up amount of fuel, run more spark advance = more power on e85. Same thing for 91. Vehicle can adjust to it, although a tune is really needed to optimize any fuel whether it's 91 or diesel.

Edited by kstruckcountry
Posted

Alright, well then that proves my point these engines ARE indeed optimized for E85, and NOT regular unleaded.

Not at all.

 

They are flex fuel vehicles. They have injectors that can flow higher than a gas only engine. The rest is programming wizardry.

Posted (edited)

Ok gotcha - now I understand!! I was under the impression that everyone was trying to convince me that engine for engine, e85 will beat gasoline. Little misunderstanding on my part.

 

And you guys friggin type a billion times faster than I do - looks like I made a few comments to posts that were already 3 comments deep ... :lol:

Edited by Jsdirt
Posted

I just went to PASS the emissions inspection during my lunch and also paid for 2 years. Very pleased with her right now!

Posted

Ok gotcha - now I understand!! I was under the impression that everyone was trying to convince me that engine for engine, e85 will beat gasoline. Little misunderstanding on my part.

 

And you guys friggin type a billion times faster than I do - looks like I made a few comments to posts that were already 3 comments deep ... :lol:

Flex fuel vehicles are set up for E85. They have the larger injectors, an ethanol sensor and have a program that runs for each fuel. it senses the difference, hence the ethanol sensor and then adjusts timing and fuel delivery accordingly.

 

Now you can run E85 but you will not get the full benefit like a flex fuel vehicle.

Posted (edited)

My truck is the LMG flex engine. I haven't run E85 personally, but just running the 20% that some unethical fuel sellers dilute the gasoline with (posted 10% at pump), kills my mileage and seat-of-the-pants power. It's very noticeable. I can tell how bad the fuel is after a fill-up about 10 minutes after I leave the station. Whenever I am out of state and find ethanol-free fuel, it seriously feels like the truck gained 50 HP at the rear wheels. Mileage goes way up as well.

 

That was the whole reason I found out I was at 20% alcohol content that one time - truck had lost so much punch that I grabbed my scan tool thinking I had some major problems about to show up. Only thing I found out of the ordinary was the higher than expected alcohol content, and the mileage I got off that tank (13 MPG, when I normally get 15-16.5) backed that up.

Edited by Jsdirt
Posted

Flex fuel vehicles are set up for E85. They have the larger injectors, an ethanol sensor and have a program that runs for each fuel. it senses the difference, hence the ethanol sensor and then adjusts timing and fuel delivery accordingly.

 

Now you can run E85 but you will not get the full benefit like a flex fuel vehicle.

From what I have researched, GM does not use an ethanol sensor anymore. It's just in the programming. Just what I've read here so no facts to quote to prove either way.

 

No as to my engine, I'm almost curious enough to try some e85 in my current engine just to see how it goes. I wouldn't expect any changes in operation except the mileage decrease but I only get 11-12mpg on regular so I don't think that would be a huge factor.

Posted

From what I have researched, GM does not use an ethanol sensor anymore. It's just in the programming. Just what I've read here so no facts to quote to prove either way.

 

No as to my engine, I'm almost curious enough to try some e85 in my current engine just to see how it goes. I wouldn't expect any changes in operation except the mileage decrease but I only get 11-12mpg on regular so I don't think that would be a huge factor.

I know on the C5 Camaro forum, upgrading the Camaro to E85 can make a nice difference and they are showing adding a sensor. I contacted Black Bear Performance and Justin stated that I need to upgrade my injectors and add a sensor and then he can tune my Camaro. Otherwise it will not get the full benefit of running it.

 

Most are finding out that E85 is a cheap source of racing fuel really. Since it is 105 octane. The big power see'ers so to speak are the ones running boosted engines, they really notice a huge difference when tuned for E85.

 

We ran it in our 2011 Acadia, which isn't flex fuel and it ran just fine, no difference in power and the mpg went down from 19 to 17. I found an app that converts the difference between gas and flex fuel and with that mpg drop and the difference in the cost per gallon, it was still cheaper to run the flex fuel.

 

We just got flex fuel in our area and as soon as my 02 Silverado gets down to a quarter tank, I'm filling it up with E85 and will be interested to see what the difference is with it.

 

I also have been in contact with Terry Dyson of Dysonanalysis. I use him for my used oil analysis. He told me that he is seeing great results with all his customers running flex fuel and improved oil analysis. Their engines are running cleaner and improved UOA's. My nitration on my 02 is really high and he said that running flex fuel should take care of that issue. I guess we will see.

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