What GM says about e85 conversions

[GMCSonoma]

Subject:Use of E85 Fuels in Vehicles Not Certified As Being FlexFuel Compatible/Aftermarket Conversion of Vehicles to Operate on E85 Fuels #06-06-04-035 - (07/13/2006)

Models:2007 and Prior GM Passenger Cars and Trucks NOT FlexFuel (E85) Compatible (including Saturn)
2007 and Prior HUMMER H2, H3
2005-2007 Saab 9-7X

Aftermarket Conversions of Vehicles to Use E85 Fuels

General Motors has become aware of several companies that claim to be able to convert vehicles equipped with gasoline engines to be compatible with E85 Fuels.

• Vehicles certified by GM as being FlexFuel (E85) compatible contain numerous calibration and component differences that are not conducive to an aftermarket retrofit.
• General Motors DOES NOT support or endorse conversions that may alter the emissions and related emissions components of its vehicles.
• Repairs that may result from changes to GM built components, and repairs that result from the use of improper fuel, such as the use of gasoline containing more than 10% Ethanol in a non-FlexFuel certified vehicle, are not covered under the terms of the New Vehicle Warranty.

A complete list of GM FlexFuel compatible vehicles can be found below or at www.livegreengoyellow.com.
2007

• 5.3L V-8 Engine Chevy Silverado and GMC Sierra Half-ton Pickups 2WD and 4WD
• 5.3L Vortec-Engine Avalanche, Suburban, Tahoe, Yukon and Yukon XL
• 3.5L Chevy Impala (LS, 1LT and 2LT)
• 3.5L Chevy Monte Carlo (LS and LT Models Only)

2006

• 3.5L Chevy Impala (LS, 1LT and 2LT)
• 3.5L Chevy Monte Carlo (LS and LT Models Only)

2005-2006

• 5.3L Vortec-Engine Avalanche
• 5.3L Vortec-Engine Police Package Tahoe

2003-2006

• 5.3L V-8 Engine Chevy Silverado and GMC Sierra Half-ton Pickups 2WD and 4WD
• 5.3L Vortec-Engine Suburban, Tahoe, Yukon and Yukon XLs

2002

• 5.3L V-8 Engine Chevy Silverado and GMC Sierra Half-ton Pickups 2WD and 4WD
• 5.3L Vortec-Engine Suburban, Tahoe, Yukon and Yukon XLs
• 2.2L Chevrolet S-10 Pickup 2WD
• 2.2L Sonoma GMC Pickup 2WD

2000-2001

• 2.2L Chevrolet S-10 Pickup 2WD
• 2.2L Sonoma GMC Pickup 2WD

[Ming]

Any technical reason why only GM's pushrod engines have this capability? Any reason why the 2.2L Ecotec couldn't run (at a reasonable cost of conversion to GM) on E-85?

[shadams]

It should be noted in that bulletin that only certain engines listed are compatible. For example not all 5.3's are compatible as the list makes you think. Only the "Z" 5.3's can use E85, also it will say on the fuel door wether or not it can use it.

[GMCSonoma]

I actually looked up in the parts catalog about the difference in parts for a 2006 Impala e85 vs a non-e85...so far as "hardware" is concerned...different injectors & different fuel tank meter/pump/module assy is all I can tell so far...fuel lines, rail, PCM all the same...

Now the $20 question...what about the PCM program!!!

[shadams]

Originally Posted by GMCSonoma

I actually looked up in the parts catalog about the difference in parts for a 2006 Impala e85 vs a non-e85...so far as "hardware" is concerned...different injectors & different fuel tank meter/pump/module assy is all I can tell so far...fuel lines, rail, PCM all the same...

Now the $20 question...what about the PCM program!!!

GM is going to say that no matter what to cover their arses, just like they say not to put big tires on Duramaxes. But whoever comes up with a way to convert these cars, including software, injectors, etc. is going to make a killing. I wish it were me.

[GMCSonoma]

Originally Posted by shadams

GM is going to say that no matter what to cover their arses, just like they say not to put big tires on Duramaxes. But whoever comes up with a way to convert these cars, including software, injectors, etc. is going to make a killing. I wish it were me.

No kidding!

[likearock00]

E-85 is no better of a deal than regular unleaded. Why go through the trouble of rigging your vehicle and voiding your warranty just to use it? I am sure there are some stupid people out there who will try, and I will laugh when I read the stories on here.

[1999 White C5 Coupe]

E85 fuel contains about two-thirds the energy of non-ethanol unleaded gasoline (gallon for gallon).

What is rarely discussed is that vehicles designed to run on E85 fuel get significantly less mileage using E85 fuel compared to using non-ethanol unleaded fuel (or fuel that has 10% or less ethanol).

Why would anyone want to convert a vehicle to run on E85 fuel and reduce their fuel mileage significantly?

GM is touting the number of new vehicles designed to run on E85 fuel, but the company does not talk about the reduced mileage.

[shadams]

Originally Posted by likearock00

E-85 is no better of a deal than regular unleaded. Why go through the trouble of rigging your vehicle and voiding your warranty just to use it? I am sure there are some stupid people out there who will try, and I will laugh when I read the stories on here.

People are obsessed with it. They dont care if it gets less mileage, they just want to use less oil. My stance is that if there are enough people who can and do use it, it will eventually lessen the demand for oil which will eventually bring the price of oil down (?) Anyway people are bound to try it, and I would if and only if there were a tried and true method thats approved by GM just to have the option. But until then I will be laughing with you as well.

[shadams]

Originally Posted by 1999 White C5 Coupe

E85 fuel contains about two-thirds the energy of non-ethanol unleaded gasoline (gallon for gallon).

What is rarely discussed is that vehicles designed to run on E85 fuel get significantly less mileage using E85 fuel compared to using non-ethanol unleaded fuel (or fuel that has 10% or less ethanol).

Why would anyone want to convert a vehicle to run on E85 fuel and reduce their fuel mileage significantly?

GM is touting the number of new vehicles designed to run on E85 fuel, but the company does not talk about the reduced mileage.

It is true what you say, but with the right tuning you can still make tons of power, as proven by the Solstice GXP drifter car which runs on E-85.
550hp and 450ft lbs of torque from a 4cyl E85 powered car. Awesome.

[jb1986_GM]

someone has come with a way to convert non E85 cars to E85 compatible. There is a guy online that has 385,000 miles on his old Century when he put in a new chip in his PCM.
http://www.youtube.com/watch?v=Uq8wdgqqKEU

[tamatt27]

Originally Posted by 1999 White C5 Coupe

E85 fuel contains about two-thirds the energy of non-ethanol unleaded gasoline (gallon for gallon).

What is rarely discussed is that vehicles designed to run on E85 fuel get significantly less mileage using E85 fuel compared to using non-ethanol unleaded fuel (or fuel that has 10% or less ethanol).

Why would anyone want to convert a vehicle to run on E85 fuel and reduce their fuel mileage significantly?

GM is touting the number of new vehicles designed to run on E85 fuel, but the company does not talk about the reduced mileage.

(Positive) facts about E85:
1. It is not corrosive to the fuel system or the engine. This is a myth and ethanol is often confused with methanol, which actually have corrosive properties. I´ve run my car for well over two years on E85 without a problem. Some models before 1988 on the other hand may have some parts that is not ethanol resistant. If we are talking Volvo´s, then this mainly applies to the non-electronically injection systems such as K-jet etc. Most cars with electronical fuel injection (EFI) should be resistant to ethanol. Some people say it would kill your engine right away and that you should buy there racefuel instead (of course they say )

2. It is not as harmful to the nature/environment as gasoline or any other petroleum products for that matter. Ethanol is made out of renewable energy resources such as crops and trees to name a few things. The carbon dioxide that an ethanol powered car emits is not contributing to the greenhouse effect, but is taken up by the plants and is being "re-used". The carbon dioxide then goes around in a closed loop. Gasoline on the other hand is made from oil that comes from old dinosaurs , plants and other stuff 100 000 of years ago, and it doesn´t take part in the closed loop but only adds to the amount of greenhouse gasses. Ethanol is also easily bio-degradeable if it should leak into our environment.

3. E85 is 104-105 octane and therefore it´s more knock-resistent and can tolerate more boost or a higher CR.

4. E85 cools the intake charge more and therefore it´s more knock-resistent and can tolerate more boost or a higher CR. And it also makes the engine run cooler and to some degree, even safer.

5. E85 is in most cases at least 5% more effícient than gasoline at the same lambda value (up to 25% more efficient on some cars optimized soley for E85). Mill your heads

6. Since E85 has very good cleaning properties as well as leaving behind a rest-product of water, it is cleaning the fuel system and it will keep the injectors nice and clean. The combustion chambers, valves, ports and the exhaust will also be clean(er), almost like the car had water injection.

7. In most cases it will cost less $/mile to run on E85.


(Negative) facts about E85:
1. Cars running on E85 have some trouble starting when the engine temperature drops below +5*C. Cars running E100 (not very common) have some trouble starting when the intake (the air) temperature is below +15*C. This is easily solved by using an engine heater in the winter, electrical or fuel-heated (this is recommended on all cars regardless of fuel to get better mileage, less wear on the engine and less impact on the environment etc., but that is another matter to discuss and will not be brought up here...). Some people also adds a little extra gasoline to the tank of E85 to help with cold-starts.

2. Since cars running E85 requires roughly 30% more fuel, a tank of E85 will not get you as far as a tank of gasoline and you will have to refuel more often. This is often disregarded by E85 users who learn to live with it because of the economical gains.

How much will my miles per gallon of fuel drop with E85?
The only negative to E85 is that it gives a lower fuel milage on a gallon for gallon basis to gasoline. The actual difference in energy content between straight gasoline and E85 is about 27%.
The drop in milage is not as significant as you would think based on that difference due to the higher effeciency of the ethanol as a high performance fuel.
The lower milage is not really a big deal, ethanol has lower energy per gallon but your reduction in milage is not nearly as large as that difference would imply. Due to the higher torque,you use slightly smaller throttle openings to get the same level of preformance, and due to the greater quantity of combustion products (more moles of gas) per lb of fuel the engine effeciency actually goes up slightly.

***Thanks fo RUNN at LS1tech.com for the info!***

[327]

Originally Posted by 1999 White C5 Coupe

E85 fuel contains about two-thirds the energy of non-ethanol unleaded gasoline (gallon for gallon).

What is rarely discussed is that vehicles designed to run on E85 fuel get significantly less mileage using E85 fuel compared to using non-ethanol unleaded fuel (or fuel that has 10% or less ethanol).

Why would anyone want to convert a vehicle to run on E85 fuel and reduce their fuel mileage significantly?

GM is touting the number of new vehicles designed to run on E85 fuel, but the company does not talk about the reduced mileage.

Actually it isnt that big of a mpg drop, and if its sold cheaper like $2 vs $3.30 then it doesnt really matter. That and what shadams said is true if you have a high compression ratio

[DuSpinnst]

As long as you have hardware in your car that supports both Gas and E85, as well as the correct PCM software then your car will run on it.

It shouldn't matter who provides the hardware.

[1999 White C5 Coupe]

Originally Posted by 327

Actually it isnt that big of a mpg drop, and if its sold cheaper like $2 vs $3.30 then it doesnt really matter. That and what shadams said is true if you have a high compression ratio

In Cincinnati Ohio, "E-85" fuel is selling for about 30 cents a gallon less than standard, regular unleaded fuel (not a $1.30 difference). The price of E-85 fuel has risen at about the same pace as regular unleaded fuel.

It will cost more to operate a vehicle with E-85 fuel than regular unleaded at that price difference, since E-85 fueled vehicles get significantly less mpg (and yes I know it has a higher octane rating).