E85 Fuel / Performance
Thread Starter
Pro
Joined: Apr 2004
Posts: 719
Likes: 21
From: Miami Fl
E85 Fuel / Performance
Yesterday I filled up for the first time my 98 vette with E85 and I noticed some power gains I usually run regular E10 fuel 87 octane. Whats incredible is that I have no issues with cold startup or any pinging even under full throttle.
Anyone else on here running E85?
The exhaust even kinda smells better..not that I purposely sniff my exhaust.
Anyone else on here running E85?
The exhaust even kinda smells better..not that I purposely sniff my exhaust.
Drifting
Joined: Dec 2006
Posts: 1,523
Likes: 5
From: Holly, Michigan
E85 is a higher octane fuel. It has an octane rating of approx 100..So, the engine will be able to advance the timing a bit, with far less change of pinging of knocking. Some import guys are running E85 specifically due to this octane improvement. However, E85 is harder on the rubber components of the fuel system and can eventually fail, causing leaks. The heating value of E85 is less than regular gasoline so fuel economy will suffer somewhat.
Thread Starter
Pro
Joined: Apr 2004
Posts: 719
Likes: 21
From: Miami Fl
I had heard something about all gm cars after 2000 have fuel systems components that can resist alcohol based fuels, but then again I am 98. The fuel economy is bad I dropped from a 16.9 combined city highway to a 11.4.
Like I said the performance is great. Let see if anyone else has ran this test and what the outcome has been. It will be really good to see if there is Gm Tech on here that can shed some more light on this matter.
Overall you save 16% on the cost of fuel per gallon but waste 32% more fuel. So you actually get some performance increase at a 15%-16% increased spending.
Well at least the money is going back into our own economy.
Like I said the performance is great. Let see if anyone else has ran this test and what the outcome has been. It will be really good to see if there is Gm Tech on here that can shed some more light on this matter.
Overall you save 16% on the cost of fuel per gallon but waste 32% more fuel. So you actually get some performance increase at a 15%-16% increased spending.
Well at least the money is going back into our own economy.
E85 is a higher octane fuel. It has an octane rating of approx 100..So, the engine will be able to advance the timing a bit, with far less change of pinging of knocking. Some import guys are running E85 specifically due to this octane improvement. However, E85 is harder on the rubber components of the fuel system and can eventually fail, causing leaks. The heating value of E85 is less than regular gasoline so fuel economy will suffer somewhat.
Safety Car
Joined: Sep 2004
Posts: 4,762
Likes: 0
I would strongly advise against this without a proper tune. I'm preparing to go to E85 since it's widely available here. According to my tuner you need to be set up properly for it (primarily a tune and maybe injectors). I would avoid going WOT at all cost. I suppose you will be OK running one tank of it through. Are you getting any codes? My best guess is you are probably runnig extremely lean. E85 requires a much fatter A/F ratio.
Thread Starter
Pro
Joined: Apr 2004
Posts: 719
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From: Miami Fl
Hmmm. Well WOT is the best part of it!
I will check tonight when i get home of there are any codes...highly doubt it since the light is off.
I have read up all the information on cars running lean since you need more content of ehenol versus regular fuel to maintain a proper ratio. But correct me if i am wrong this only applies to carburated cars that have no way of electronically altering their fuel mix. In most corvettes after 84 they have at least dual O2 sensors that immediatlly detect a lean condition and alter the pulse rate and duration of the injector to compensate for the lean condition to be corrected. The only time the exhaust / 02 sensors are not working is while the coputer is running in open loop which is only when engine temps are under 145. So a WOT run with your engine in open loop will cause a lean condition that can lead to damage, but then again its not really smart to be doing WOT runs before your engine reaches normal running temps.
By the way i am going to see if i borrow my friends scan tool and it should give me accurate readouts of 02 sensors voltages and timing advance.
let me know what you think.
I will check tonight when i get home of there are any codes...highly doubt it since the light is off.
I have read up all the information on cars running lean since you need more content of ehenol versus regular fuel to maintain a proper ratio. But correct me if i am wrong this only applies to carburated cars that have no way of electronically altering their fuel mix. In most corvettes after 84 they have at least dual O2 sensors that immediatlly detect a lean condition and alter the pulse rate and duration of the injector to compensate for the lean condition to be corrected. The only time the exhaust / 02 sensors are not working is while the coputer is running in open loop which is only when engine temps are under 145. So a WOT run with your engine in open loop will cause a lean condition that can lead to damage, but then again its not really smart to be doing WOT runs before your engine reaches normal running temps.
By the way i am going to see if i borrow my friends scan tool and it should give me accurate readouts of 02 sensors voltages and timing advance.
let me know what you think.
I would strongly advise against this without a proper tune. I'm preparing to go to E85 since it's widely available here. According to my tuner you need to be set up properly for it (primarily a tune and maybe injectors). I would avoid going WOT at all cost. I suppose you will be OK running one tank of it through. Are you getting any codes? My best guess is you are probably runnig extremely lean. E85 requires a much fatter A/F ratio.
Safety Car
Joined: Sep 2004
Posts: 4,762
Likes: 0
That makes perfect sense but the problem in this case is the computer is not programmed for e85 like many of the current gm flex fuel vehicles. Not trying to **** in your cornflakes or anything, just would hate to see you fry your motor. Give Ron a Pro Dyno Tech a call 765-225-1718 . He tunes for e85 and could give you a much better explaination and understanding of running e85 in the vettes.
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Thread Starter
Pro
Joined: Apr 2004
Posts: 719
Likes: 21
From: Miami Fl
Haha pissing in my flakes thats funny!
OK that sounds good i'll give him a ring...some things you just have to leave to the pros.
let me know how yours goes once you get it done. Especially if you dyno it. The reason i started this thread is beacuse i really think these fuels are going to get cheaper and better with this new admistration thats starting next year.
Plus the C6R uses it so you know its good!
OK that sounds good i'll give him a ring...some things you just have to leave to the pros.
let me know how yours goes once you get it done. Especially if you dyno it. The reason i started this thread is beacuse i really think these fuels are going to get cheaper and better with this new admistration thats starting next year.
Plus the C6R uses it so you know its good!
That makes perfect sense but the problem in this case is the computer is not programmed for e85 like many of the current gm flex fuel vehicles. Not trying to **** in your cornflakes or anything, just would hate to see you fry your motor. Give Ron a Pro Dyno Tech a call 765-225-1718 . He tunes for e85 and could give you a much better explaination and understanding of running e85 in the vettes.
Safety Car
Joined: Sep 2004
Posts: 4,762
Likes: 0
Haha pissing in my flakes thats funny!
OK that sounds good i'll give him a ring...some things you just have to leave to the pros.
let me know how yours goes once you get it done. Especially if you dyno it. The reason i started this thread is beacuse i really think these fuels are going to get cheaper and better with this new admistration thats starting next year.
Plus the C6R uses it so you know its good!
OK that sounds good i'll give him a ring...some things you just have to leave to the pros.
let me know how yours goes once you get it done. Especially if you dyno it. The reason i started this thread is beacuse i really think these fuels are going to get cheaper and better with this new admistration thats starting next year.
Plus the C6R uses it so you know its good!
Melting Slicks
Joined: Nov 2003
Posts: 3,011
Likes: 9
From: Dublin GA
From what I have read, I'd have to agree with MJD. The PCM can compensate to some extent at part throttle, but at WOT, the O2 sensors don't affect the mixture, it is a values based on your PE multiplier. That being the case, you probably would go lean
Once again I'm not sure, but you may even have to change to larger injectors if you have any mods.
Your performance gains may be coming from the fact that your car is probably having to run retarded timing from the 87 gas
Compression on these cars dictate 93
The thermal efficiency of E85 is well below gas. That's evident by the simple fact that you are getting much worst fuel mileage.
I would DIFINTLY check the AFR at WOT, before doing to many more spirited runs. Just my .02
Once again I'm not sure, but you may even have to change to larger injectors if you have any mods.Your performance gains may be coming from the fact that your car is probably having to run retarded timing from the 87 gas
Compression on these cars dictate 93The thermal efficiency of E85 is well below gas. That's evident by the simple fact that you are getting much worst fuel mileage.
I would DIFINTLY check the AFR at WOT, before doing to many more spirited runs. Just my .02
Thread Starter
Pro
Joined: Apr 2004
Posts: 719
Likes: 21
From: Miami Fl
Your right the o2 sensors do not operate at WOT. Yeah i do have some mods no cats,long tube headers,varam intake (which is making even leanner i bet).
What do the set of injectors go for? anyone have this info or their specs?
What do the set of injectors go for? anyone have this info or their specs?
From what I have read, I'd have to agree with MJD. The PCM can compensate to some extent at part throttle, but at WOT, the O2 sensors don't affect the mixture, it is a values based on your PE multiplier. That being the case, you probably would go lean Once again I'm not sure, but you may even have to change to larger injectors if you have any mods.
Your performance gains may be coming from the fact that your car is probably having to run retarded timing from the 87 gas Compression on these cars dictate 93
The thermal efficiency of E85 is well below gas. That's evident by the simple fact that you are getting much worst fuel mileage.
I would DIFINTLY check the AFR at WOT, before doing to many more spirited runs. Just my .02
Once again I'm not sure, but you may even have to change to larger injectors if you have any mods.Your performance gains may be coming from the fact that your car is probably having to run retarded timing from the 87 gas
Compression on these cars dictate 93The thermal efficiency of E85 is well below gas. That's evident by the simple fact that you are getting much worst fuel mileage.
I would DIFINTLY check the AFR at WOT, before doing to many more spirited runs. Just my .02
Le Mans Master
Joined: Sep 2003
Posts: 8,847
Likes: 795
From: Longview Texas
I would hesitate to run any alcohol content above the nominal 10% in any car that does not have a fuel system designed for it.
As already noted, the octane is higher, but you will burn more gallons, so you most likely will not be saving any money. Why risk it?
I still look for stations that say their gasoline contains NO ETHANOL, like the local Texaco station, which also has Techron.
As already noted, the octane is higher, but you will burn more gallons, so you most likely will not be saving any money. Why risk it?
I still look for stations that say their gasoline contains NO ETHANOL, like the local Texaco station, which also has Techron.
Last edited by TEXHAWK0; Nov 17, 2008 at 05:40 PM.
Melting Slicks
Joined: Apr 2003
Posts: 2,150
Likes: 6
From: NS
If the car wasn't designed for E85 then you're playing with fire. Why do you think GM designs vehicles specifically for E85 and uses the term "FlexFuel"? They also give them a nice yellow E85 gas cap (newer models).
http://environmentpsychology.com/is_..._e85_ready.htm
http://www.e85fuel.com/e85101/faqs/anycar.php
At WOT you're no longer in closed loop and you risk burning pistons, etc. Big risk if you ask me.
http://environmentpsychology.com/is_..._e85_ready.htm
http://www.e85fuel.com/e85101/faqs/anycar.php
At WOT you're no longer in closed loop and you risk burning pistons, etc. Big risk if you ask me.
Last edited by Atok; Nov 17, 2008 at 06:32 PM.
Racer
Joined: Oct 2004
Posts: 480
Likes: 16
From: chicago il
One of the problems with e-85 around chicago is they change the blend of the fuel with the seasons while it doesnt effect me but some of my friends with blower/turbo cars that run the e-85 you never know what blend your getting.. Ive been told the winter/fall blends contain as much as 15% less.. This can be a huge problem for a blower car that was tuned with the spring/summer blend...
Finally I really hope this fuel takes off it will be nice to actually see The american farmers thriving again...
Finally I really hope this fuel takes off it will be nice to actually see The american farmers thriving again...
Pro
Joined: Oct 2007
Posts: 607
Likes: 29
From: Tulsa Oklahoma
The gain in performance is probably due to the fact that you were running regular to begin with. Corvettes use premium. You were probably getting knock with the regular causing the computer to pull timing. I would put premium in the car.
Heel & Toe
Joined: Mar 2008
Posts: 19
Likes: 0
From: Andover MN
One other thing is that it is a full flex fuel. I have run on 92 octane and ran fine. You can do this when your low on fuel and it will learn to run on either. It favors E-85 more then the 92 octane and high the octane the better.