E85 conversion?

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rockola1971

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Depending on how little E85 costs in your area, it may make sense to run it even though you get less mpg. and for those interested in performance, well, it does allow the motors to make more power.

It makes "more power"? Impossible since the BTU output of 87 octane is substantially higher than E-85. Science doesnt lie. E-85 is useful in a high compression engine application due to its over 100 octane rating so it will resist detonation. But there absolutely zero logic in running E85 in a everyday driver, it WILL cost you more each mile driven running on E85. 15-25% less mileage on E-85 vs 87 octane. Math doesnt lie either.
 

schaffer05

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It makes "more power"? Impossible since the BTU output of 87 octane is substantially higher than E-85. Science doesnt lie. E-85 is useful in a high compression engine application due to its over 100 octane rating so it will resist detonation. But there absolutely zero logic in running E85 in a everyday driver, it WILL cost you more each mile driven running on E85. 15-25% less mileage on E-85 vs 87 octane. Math doesnt lie either.
Many people have run dynos on their tuned vehicles with E85, and their results contradict your statements.


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swathdiver

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It makes "more power"? Impossible since the BTU output of 87 octane is substantially higher than E-85. Science doesnt lie. E-85 is useful in a high compression engine application due to its over 100 octane rating so it will resist detonation. But there absolutely zero logic in running E85 in a everyday driver, it WILL cost you more each mile driven running on E85. 15-25% less mileage on E-85 vs 87 octane. Math doesnt lie either.

General Motors has posted dyno results of the LC9 engine with and without E85 and it makes about 6 more horsepower. The computer detects the E85 and alters the computer's parameters to allow it to make more power. Not all E85 is over 100 octane anymore either.

Finally, cost efficiency depends on how much one pays for gasoline and the mileage they get and how much they pay for E85 and they mileage they get with that. Despite my truck getting less miles per gallon with E85, I saved about 1 1/2 cents per gallon as the fuel cost less. In my case this was only done one time because of the hurricane but if E85 continues to be available where I live, and at a good price, I might just start using it.
 

about20ninj45

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There is a thread on pt.net that I started that has all the info you are looking for to convert to e85. Basically you will need the OS from a flex fuel vehicle, e85 fuel sensor, e85 pump, injectors and e85 fuel lines. Gains to be had depends on how much timing you are running. Typical gains are 20-50 more HP over 87 octane due to e85 cooling benefactor, which also keeps detonation down.
 

retiredsparky

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The one factor you guys are leaving out is the very common failure of that E85 sensor, which is quite expensive ($300-$450)
 

ezstriper

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no gain what so ever, now if you were going to add boost then by all means, been racing a LS turbo car on E85 for years, in the E85 cant be beat(we run 26psi and no intercooler) but stock no gain at all, you need to burn about 30% more
 
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rockola1971

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Anyone here wonder why a flex fuel 5.3L uses the 6.0L fuel injectors INSTEAD of the standard non flex fuel (smaller) injectors? Theres a reason...Because it takes more e-85 to do the same amount of work 87 octane can do. 6.0L injectors provide a higher lb/hr flow rate than the standard injectors.

If you build a engine for E-85 with higher compression and even a Turbo then yes it will make more power. Substantially more but It wont be getting the gas mileage your non E85 engine will driving back and forth to work and dropping by the grocery store.
 

rockola1971

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General Motors has posted dyno results of the LC9 engine with and without E85 and it makes about 6 more horsepower. The computer detects the E85 and alters the computer's parameters to allow it to make more power. Not all E85 is over 100 octane anymore either.

Finally, cost efficiency depends on how much one pays for gasoline and the mileage they get and how much they pay for E85 and they mileage they get with that. Despite my truck getting less miles per gallon with E85, I saved about 1 1/2 cents per gallon as the fuel cost less. In my case this was only done one time because of the hurricane but if E85 continues to be available where I live, and at a good price, I might just start using it.

I dont dispute that E-85 is "cheaper" but it is not cheap enough to overcome the MPG losses that come with E-85 to make it cost less per mile driven with 87 octane. Your math is flawed.
 

about20ninj45

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Anyone here wonder why a flex fuel 5.3L uses the 6.0L fuel injectors INSTEAD of the standard non flex fuel (smaller) injectors? Theres a reason...Because it takes more e-85 to do the same amount of work 87 octane can do. 6.0L injectors provide a higher lb/hr flow rate than the standard injectors.

If you build a engine for E-85 with higher compression and even a Turbo then yes it will make more power. Substantially more but It wont be getting the gas mileage your non E85 engine will driving back and forth to work and dropping by the grocery store.



Your information is a lil off,
99-00 injectors are 22lbs
01-06 4.8/5.3/6.0 25-27lbs
8.1 truck injectors are 30lbs
8.1 marine injectors are 42lbs

Flex fuel 33.5lbs
 

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