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Fuel E85 conversion necessities

  • Thread starter Thread starter paddyrk
  • Start date Start date Apr 15, 2020
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    e85 ethanol flex fuel turbo

paddyrk

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Apr 15, 2020
#1
  • Apr 15, 2020
  • #1
I have a 1991 5.0 LX, with a 347 stroker swap making 325 whp with a manual valve body aod. I have plans to go turbo with the same internals as I had for NA (yes they can support my power goals), ~10.5:1 compression, and I want ~450whp, I'll only need a couple pounds of boost, but I want to see if I can run e85 to ensure no knock, and cooler temperatures.

What do I need to replace to keep my car safe on e85?
I have an aftermarket fuel pressure regulator, new fuel rails from jegs, and some rubber lines in place of the steel lines at the ends.
I will be getting an e85 safe pump from on3 performance.
I need bigger injectors, but I don't know if I need e85 specific ones.
I have a Holley ECU and a sensor that can support flex fuel.
Will the gas tank be able to hold it?

Thanks guys.
 

jrichker

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#2
  • Apr 17, 2020
  • #2
There is no such thing as a "little boost". It is addictive, just like a lot of things that are fun but perilous...

You best answer is 93 octane pump gasoline and a water/alcohol injection system. it is a lot easier and cheaper than E85. Besides, if you run out of fuel while having fun, almost any gas station will do well enough to get you home .
 
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paddyrk

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Jun 7, 2018
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Apr 17, 2020
#3
  • Apr 17, 2020
  • #3
jrichker said:
There is no such thing as a "little boost". It is addictive, just like a lot of things that are fun but perilous...

You best answer is 93 octane pump gasoline and a water/alcohol injection system. it is a lot easier and cheaper than E85. Besides, if you run out of fuel while having fun, almost any gas station will do well enough to get you home .
Click to expand...
Luckily I’m running it as flex fuel with an ethanol sensor, my question is not whether I should do it, it’s what Stock components would be eaten away by e85, I have some aluminum fittings as well.
 

2000xp8

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#4
  • Apr 18, 2020
  • #4
I had read this a while back.
Should help a little.

Clearing Up Myths About E85 And Ethanol: 16 Things You Need To Know

Technical expert Jeff Smith sorts out the details of using E85 and deciphers some of the myths. If you want to get on the corn, this article is for you!
www.enginelabs.com

With the need for extra capacity, I can't see how the effort would be worth it.
Maybe if you were building something with a race block that needed a fuel system anyway, but with a 450rwhp goal, I personally don't see the point.
 
Last edited: Apr 18, 2020

a91what

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  • Apr 18, 2020
  • #5
going thru the effort of doing e85 on a 450rwhp engine is.. ah nevermind.

just use 10psi 29* timing and pull 1* per pound to start and shoot for an 11.8 AFR in boost until you have the table worked out. once fuel is tuned back it off to 12-12.3 AFR and bump the timing from 1*per to .75* per..
call it a day and enjoy your easy 450rwhp on pump gas.
 

paddyrk

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Jun 7, 2018
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Dublin, OH
Apr 18, 2020
#6
  • Apr 18, 2020
  • #6
2000xp8 said:
I had read this a while back.
Should help a little.

Clearing Up Myths About E85 And Ethanol: 16 Things You Need To Know

Technical expert Jeff Smith sorts out the details of using E85 and deciphers some of the myths. If you want to get on the corn, this article is for you!
www.enginelabs.com

With the need for extra capacity, I can't see how the effort would be worth it.
Maybe if you were building something with a race block that needed a fuel system anyway, but with a 450rwhp goal, I personally don't see the point.
Click to expand...
I already have new rails, do I need to replace the hard fuel lines underneath the car, and are there specific injectors for ethanol
 

2000xp8

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Apr 18, 2020
#7
  • Apr 18, 2020
  • #7
I don't think you need special injectors, but you could need a ridiculously large set.
My guess is also that the stock fuel lines won't be large enough.
They support just over 500rwhp with standard gas, you need to be able to supply 600rwhp worth.
 

paddyrk

Member
Jun 7, 2018
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Dublin, OH
Apr 18, 2020
#8
  • Apr 18, 2020
  • #8
2000xp8 said:
I don't think you need special injectors, but you could need a ridiculously large set.
My guess is also that the stock fuel lines won't be large enough.
They support just over 500rwhp with standard gas, you need to be able to supply 600rwhp worth.
Click to expand...
Okay, thank you for the info, did not realize that was their capacity
 
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