Burning E85 in non-E85 equipped vehicles.. pro's and cons?

[RapidG8GXP]

Charlie,

Can you list the pro's and con's to running E85 in vehicles not specifically equipped from the factory to run this type of fuel?

Some say it's ok to run E85 and that it will cause no long term damage to fuel system components in the G8, some say it won't.

What's your take on this subject?

Thanks in advance for your time.

[GRRRR8]

I knew I was going to be asked about this. Here is my opinion:

1. The fuel pump, injectors and regulator will have to be changed
2. Comparing 2 Chevy trucks (one with, one without E85) the fuel lines were the same.
3. Tuning will be the hardest part, BUT if you have the correct components I cant see it being too bad for a experienced tuner.
4. Yes it will make more power. Its been proven on multiple manufacturers at HP levels upwards of 800RWHP.
5. Will I do it....NO. Will I continue to read about it and see where E85 takes us in the future.....YES.

I feel we need to see a whole lot more locations to get E85. I dont have 1 anywhere near me (that I know of). I would advise on long trips to map out locations to get E85 as once you switch you switched. Using it for HP gains is much different then your common Flex Fuel system that comes from the factory.

[Scalarrthu]

I'd ask what are you using it for, like Charlie said is it for more power, or just for a cheaper fuel? If you run e85 plan on using much more of it, in turn causing you to get much worse gas mileage...so the difference between the price and having to run more fuel would be a wash.

I know of a couple 1000hp Supras (as well as other high hp cars) that run e85 and have no issues with it. I plan on running e85 in my Syclone, but would never switch over in my daily driver.

[WickedMom]

FWIW a few people must of asked the General this question... Here is the response.

#05-06-04-035C: Usage of E85 Fuels in GM Vehicles - (Jul 30, 2007)

Subject: Usage of E85 Fuels in GM Vehicles

Models: 1997-2008 GM Passenger Cars and Trucks (including Saturn)
2003-2008 HUMMER H2
2006-2008 HUMMER H3
1997-2008 Isuzu NPR Commercial Medium Duty Trucks
2005-2008 Saab 9-7X

This bulletin is being revised to add the 2008 model year and additional engines with E85 capability. Please discard Corporate Bulletin Number 05-06-04-035B (Section 06 -- Engine/Propulsion System).
Customer Interest in E85 Fuel

As the retail price of gasoline increases, some locations in the country are seeing price differentials between regular gasoline and E85 where E85 is selling for substantially less than regular grade gasoline. One result of this is that some customers have inquired if they are able to use E85 fuel in non-E85 compatible vehicles.

Important: Only vehicles designated for use with E85 should use E85 blended fuel.

E85 compatibility is designated for vehicles that are certified to run on up to 85% ethanol and 15% gasoline. All other gasoline engines are designed to run on fuel that contains no more than 10% ethanol.

Notice: Use of fuel containing greater than 10% ethanol in non-E85 designated vehicles can cause driveability issues, service engine soon indicators as well as increased fuel system corrosion.
Using E85 Fuels in Non-Compatible Vehicles

General Motors is aware of an increased number of cases where customers have fueled non-FlexFuel designated vehicles with E85. Fueling non-FlexFuel designated vehicles with E85, or with fuels where the concentration of ethanol exceeds the ASTM specification of 10%, will result in one or more of the following conditions:
• Lean Driveability concerns such as hesitations, sags and / or possible stalling.
• SES lights due to OBD codes.
• Fuel Trim codes P0171 and / or P0174.
• Misfire codes (P0300).
• Various O2 sensor codes.
• Disabled traction control or Stability System disabled messages.
• Harsh / Firm transmission shifts.
• Fuel system and / or engine mechanical component degradation.

Notice: Use of fuel containing greater than 10% ethanol in non-E85 designated vehicles can cause driveability issues, service engine soon indicators as well as increased fuel system corrosion.

If the dealer suspects that a non-FlexFuel designated vehicle brought in for service has been fueled with E85, the fuel in the vehicle's tank should be checked for alcohol content with tool J 44175. If the alcohol content exceeds 10% , the fuel should be drained and the vehicle refilled with gasoline - preferably one of the Top Tier brands.

Repairs to non-FlexFuel vehicles that have been fueled with E85 are not covered under the terms of the New Vehicle Warranty.

A complete list of GM’s FlexFuel vehicles can be found in this Service Bulletin, or at www.livegreengoyellow.com.
E85 Compatible Vehicles

The only E85 compatible vehicles produced by General Motors are:
• 2000-2002 S-Series pickups with 2.2L (VIN 5- RPO L43)
• 2002-2005 full-size pickups and utilities with 5.3L (VIN Z -- L59)
• 2006 Chevrolet Avalanche, Silverado, Suburban, Tahoe with 5.3L (VIN Z -- RPO L59)
• 2006-2007 Chevrolet Impala, Monte Carlo with 3.5L (VIN K -- RPO LZE)
• 2007 Chevrolet Avalanche, Suburban, Tahoe with 5.3L (VINs 0, 3 -- RPOs LMG, LC9)
• 2007 Chevrolet Express, GMC Savana with 5.3L (VIN Z-- RPO L59)
• 2008 Chevrolet Impala with 3.9L (VIN 3-- RPO LZG)
• 2006 GMC Sierra, Yukon, Yukon XL with 5.3L (VIN Z -- RPO L59)
• 2007 GMC Yukon, Yukon XL with 5.3L (VINs 0, 3 -- RPOs LMG, LC9)
• 2007 Saturn Relay, Buick Terraza, Chevrolet Uplander, Pontiac Montana SV6 (Canada Only) with 3.9L (VIN W -- RPO LGD)

Notice:
• Only vehicles that are listed in the E85 Compatible Vehicles section of this bulletin and/or www.livegreengoyellow.com are E85 compatible.
• All other gasoline and diesel engines are NOT E85 compatible.
• Use of fuel containing greater than 10% ethanol in non-E85 designated vehicles can cause driveability issues, service engine soon indicators as well as increased fuel system corrosion.
• Repairs to non-FlexFuel vehicles that have been fueled with E85 are not covered under the terms of the New Vehicle Warranty.

[lsxfanatic]

The above response with the GM tech note confuses the situation because it assumes no tuning was done on the car. You cannot just put e85 in a non flex fuel car and expect it to run correctly and not cause any damage. I think the original poster understood that some tuning would need to be done at a minimum.

There are several pros to e85 for a performance engine.
- It has much higher effective octane than high octane pump gasoline
- It burns much cleaner (keeping combustion chamber clean and free of carbon)

The Cons are:
- It has has less energy by vol compared to gasoline gas = 124k BTU e85=80k
- more corrosive than gasoline
- absorbs water quickly

So on a stock engine, you won't see great gains from e85. Mainly because the compression ratio is not that high to begin with. You can squeeze a little more out of it by bumping up the timing... A total guess here, but I would say you could see 15-30 additional rwhp on a dyno. The higher the dynamic compression ratio of the motor, the bigger gains you will see over gasoline. On a forced induction engine you can see extreme gains as you can run significantly more boost without detonation. Any power adder will be much safer on e85 vs gasoline as long as it has enough fuel.

A big downside is you need more fuel. So bigger injectors and a better fuel pump than you would need with gasoline. Once you get into big power 700rwhp and up, it is hard to get a fuel system setup that is up to the task and still daily driver friendly.

On a mostly stock car, the stock injectors and pump should have enough capacity to do the job.

The subject of the stock components being safe on e85 is still extremely controversial.

[G8 Ray]

It doesn't confuse anything. It states no warranty repairs will be made if it's found E85 was in the tank. What's confusing about that?

[lsxfanatic]

It doesn't confuse anything. It states no warranty repairs will be made if it's found E85 was in the tank. What's confusing about that?

Ok, if you are looking at it that way. Don't do anything to your car beyond maybe a CAI and catback (and to be honest that can void your warranty also). Yes, you can change the filter without issue, but a new intake track will technically void the warranty (although most dealers would let it fly unless it was as obvious as water ingestion).

Like any other performance modification, there are pros and cons to running e85. One con would be that it technically voids the warranty on the motor, but like I said before, so does just about every performance modification.

I said the tech bulletin is confusing to the original question because it was a response to a bunch of numb nuts putting e85 in their non flex-fuel cars since it was much cheaper than gasoline (at the time). These were people trying to save a buck, not performance enthusiast trying to make their motor put out more power. The flex fuel cars automatically adjust the fueling based on the alcohol content. Our cars have the potential to do this also, but it requires some changes in the tune. Not tuning the car for it or enabling the flex fuel adaptive behavior will cause all types of driveability issues and SES lights to come on.

Just go to your local track and check out the cars running e85. You will notice that they all run significantly better than their non e85 counterparts. These are usually your more hardcore guys. The casual enthusiast is probably better off sticking with gasoline.

[Robert@KBXPerformance]

Ok, if you are looking at it that way. Don't do anything to your car beyond maybe a CAI and catback (and to be honest that can void your warranty also). Yes, you can change the filter without issue, but a new intake track will technically void the warranty (although most dealers would let it fly unless it was as obvious as water ingestion).

Like any other performance modification, there are pros and cons to running e85. One con would be that it technically voids the warranty on the motor, but like I said before, so does just about every performance modification.

I said the tech bulletin is confusing to the original question because it was a response to a bunch of numb nuts putting e85 in their non flex-fuel cars since it was much cheaper than gasoline (at the time). These were people trying to save a buck, not performance enthusiast trying to make their motor put out more power. The flex fuel cars automatically adjust the fueling based on the alcohol content. Our cars have the potential to do this also, but it requires some changes in the tune. Not tuning the car for it or enabling the flex fuel adaptive behavior will cause all types of driveability issues and SES lights to come on.

Just go to your local track and check out the cars running e85. You will notice that they all run significantly better than their non e85 counterparts. These are usually your more hardcore guys. The casual enthusiast is probably better off sticking with gasoline.

Thanks, you saved me some time. Sooo... +1

[WickedMom]

Sorry if I confused anyone.

[lsxfanatic]

Sorry if I confused anyone.

No worries, the only reason I said anything is that people will see something "official" like that and run with it without considering the context.