Flex Fuel
Thread Starter
Melting Slicks
Joined: Dec 2012
Posts: 2,312
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From: Frisco Texas
Flex Fuel
Hey guys I was recently discussing going to E85 with so buddies and I wanted to know what options we had with Flex Fuel. If you tune for E85 and put 93 in will the computer compensate?
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From: Southern Ca
Melting Slicks
Joined: Jul 2005
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From: Mt. Pleasant S.C.
Our computers will not automatically compensate as we do not have a sensor for the computer to determine the difference in the fuel in the system. Flex fuel cars do have this. Ours do not.
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Burning Brakes
Joined: Apr 2010
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From: Winston Ga.
If its cheaper gas you want the cost gets negated by the worse MPG.
Maybe there is some racing reason for E85 Im not aware of?
Thread Starter
Melting Slicks
Joined: Dec 2012
Posts: 2,312
Likes: 8
From: Frisco Texas
Melting Slicks
Joined: Jul 2005
Posts: 2,990
Likes: 346
From: Mt. Pleasant S.C.
It burns cooler. You'll never notice it. what's a couple hundred degrees when you're over 2000?
There are a lot of pros and cons to running e85. Pros: You can tune for higher horsepower. Sometimes A lot more power. Used to be cheaper. Not so much anymore. marginally cooler burning.
Cons: You get worse fuel mileage. It's hygroscopic so water is always an issue. It's corrosive, so fuel pumps, injectors, etc have much less duty life. There are not a hell of a lot of e pumps out there so if you travel then you have to run your tank empty, re-tune back to 93 or 91 gas and fill with that. And my experience has been that the quality of e is different from station to station, and sometimes tank load to tank load at the same station. You need a lot more volume, so often that means different injectors to fully take advantage of it.
To me it isn't worth the effort. I travel too far and am not interested in messing with my tune often. For some people though, that extra level of performance is well worth it.
There are a lot of pros and cons to running e85. Pros: You can tune for higher horsepower. Sometimes A lot more power. Used to be cheaper. Not so much anymore. marginally cooler burning.
Cons: You get worse fuel mileage. It's hygroscopic so water is always an issue. It's corrosive, so fuel pumps, injectors, etc have much less duty life. There are not a hell of a lot of e pumps out there so if you travel then you have to run your tank empty, re-tune back to 93 or 91 gas and fill with that. And my experience has been that the quality of e is different from station to station, and sometimes tank load to tank load at the same station. You need a lot more volume, so often that means different injectors to fully take advantage of it.
To me it isn't worth the effort. I travel too far and am not interested in messing with my tune often. For some people though, that extra level of performance is well worth it.
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... I've seen some people personally have good results with it but the inconsistency and lack of stations keeps me away from it... why not use meth instead?
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well if you're boosted you have to choose one of the two lol... 100% meth and 93 was the better option for me, the only negative is you will have to send the pump out to be resealed every couple years or so... it's cheap and available in my area and I can fill up a couple of 5 gallon jugs and it lasts a good while... I keep a 1 gallon jug of it in the trunk area just in case I run low while on the street
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you could do that too... as far as a tune for pump gas or e85 the only thing I can think of is if you have hptuners you could have 2 different tunes and carry the laptop with you and reflash the pcm depending on what fuel you use but that seems like a pita to me... I guy I work with had a turbo mustang and he had something on his with like 3 or 4 different tunes and all he had to do was hit a button to switch between them but as far as I know we don't have anything like that for our cars... if you decide to run strictly e85 you will have to drive short distances or plan your trips around e85 stations or maybe get some drums and fill them up and leave them in the garage so you always have some available, not to mention you will probably have to redo your fuel system in order to use it... just seems like too much work to me for what you get out of it