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FE Power Forums => Non-FE Discussion Forum => Topic started by: Stangman on April 27, 2026, 10:19:47 PM

Title: E-85
Post by: Stangman on April 27, 2026, 10:19:47 PM
I believe this has been talked about before but what does it entail to run E-85. Is it as simple as jetting up the carb to run richer.
Title: Re: E-85
Post by: Stangman on April 28, 2026, 10:13:19 PM
I’m going to assume nobody runs e-85
Title: Re: E-85
Post by: blykins on April 29, 2026, 06:29:43 AM
I don't have a lot of experience with it, but the fuel system needs to be E-85 proof. 
Title: Re: E-85
Post by: 1964Fastback on April 29, 2026, 06:39:30 AM
I don't have direct experience either, but I've read that "E-85" can be "up to" 85% alcohol but supposedly it varies quite a bit from station to station and maybe even batch to batch.  E-85 compatible vehicles are able to sense the burn rate (or whatever) and automatically adjust the A/F mixture but with a carburetor, it seems like you'd have to be be much more certain of what you were running.  Might be doable for a race only situation?

Pat
Title: Re: E-85
Post by: TJ on April 29, 2026, 07:36:25 AM
Besides being ethanol proof and re-tuning your carb, you also need a way to deal with or prevent gelling caused by ethanol in the gas.  10% ethanol fuel gels bad enough after just a few weeks of inactivity.  The gelling doesn't seem to affect port injection as much as carburetors. 

For optimum performance probably want to increase compression a bit and adjust timing curve but good luck with that if the % ethanol jumps up and down from batch to batch.
Title: Re: E-85
Post by: pbf777 on April 29, 2026, 10:37:22 AM
Is it as simple as jetting up the carb to run richer.

     Perhaps a nice start, but "no"!   :(

. . . . . the fuel system needs to be E-85 proof. 

     Very true!   :)

I've read that "E-85" can be "up to" 85% alcohol but supposedly it varies quite a bit from station to station and maybe even batch to batch. 

     Correct!  And a problem if your purpose was to convert to E85 for the "anti-knock" qualities, as this varies with the "mix"!  Testing kits have been created, though I'm not well aware of their accuracy, this to be utilized with each fill-up to determine if a "tune" change might be in order; this both for detonation avoidance and A/F mixture needs.   :o

You also need a way to deal with or prevent gelling caused by ethanol in the gas.  10% ethanol fuel gels bad enough after just a few weeks of inactivity.  The gelling doesn't seem to affect port injection as much as carburetors.


     Again correct!  Fuel injection (as currently supplied by the O.E.M.'s) is a "sealed fuel system", this reducing the fuels exposure to the atmosphere.  The biggest issue is that the alcohol, being hygroscopic draws moisture from the atmosphere and will continue to do so until saturated.  Now, if that isn't bad enough, but then the alcohol is also highly evaporative, so with an "open" or "vented" fuel system it tends to dissipate into the atmosphere, but leaving the water behind and this becomes the headache stuff!    >:( 

     Also consider that if the fuel delivery system, pump(s), filter(s), fuel lines, possibly regulation and even the carburetor, is currently properly balanced for gasoline, it will prove "insufficient", this probably beyond just a "jet-change", for E85.   ;)

    And then yeah,  alcohol is lower in it's B.T.U. production in the combustion cycle, and why it requires significantly more by volume, so unless your combination would benefit from E85 in order to capitalize on a more aggressive state of tune, the net result could be less power!   :-[

     Scott.
Title: Re: E-85
Post by: thatdarncat on April 29, 2026, 12:59:11 PM
I don’t have any personal experience, but follow the subject casually like some others. Getting a little deeper into the question is probably warranted, as others touched on.

Why are you thinking about E85? How are you using the vehicle - race, street toy, more daily driver?

Are you planning on using pump E85 at random filling stations, or buying dedicated E85 barrels from a fuel supplier?


There are now quite a few “Drag & Drive” type events, similar to Hot Rod Drag Week, around the U.S. every year, and quite a few competitors that run E-85, especially if it’s available near the route, if there’s one of these events near you it might be a good idea to check one out and talk to the participants for their experience. Most folks like talking about their combination, providing they’re not deep in a mad thrash. And I do know, like already mentioned, those people all carry E-85 test kits with them, to monitor what they’re getting at the local station, which is why the question of what you plan to use is important.
Title: Re: E-85
Post by: mbrunson427 on April 29, 2026, 02:58:33 PM
Joe, I have looked into this quite a bit. Not really because I plan to use it in anything, but more because of intrigue and learning.

Here's where I stand: If I were to run E-85 I don't believe I'd buy pump E-85. I would be sourcing it through Ignite Racing Fuel or similar. This is because the pump fuel seems to gum up and after sitting for the offseason would require at bare minimum the carb to be cleaned up. Ignite claims that their fuel wont do this. The bad part is this would kind of take the streetability out of the car unless you want to drive around with a jug of it in your trunk.

If you have the time, listen to this podcast
https://www.youtube.com/watch?v=LjtFGgGLvok&t=28s
Title: Re: E-85
Post by: Stangman on May 01, 2026, 10:32:21 PM
Thank you guys for all the responses. I haven’t been able to get on the forum for three days it wouldn’t hook me up to server. Maybe my iPad is getting old. All my friends use e-85 but most of them are fuel injected and one is a blow through carb. My fuel system is good enough to use it but I’m not sure I would like it sitting in my carb for any length of time. I really only put around 2 to 300 miles on my car a year and go to the track 3 times a year but Im under the impression it’s got more octane in it. Like Mike said not sure I would use it but was curious
Title: Re: E-85
Post by: Jim Kramer on May 02, 2026, 11:14:30 AM
I have used pump E85 for several years in my Mustang There are advantages and disadvantages , The consistency is a problem, I have a retard set in the MSD box in case I get a poor batch of fuel, but the bigger problem for you would be your intermittent usage of the car, If its gonna sit for more than a week or two you would really need to dump the carb, The alcohol will eventually attack the metal_______Jim Kramer 
Title: Re: E-85
Post by: Stangman on May 02, 2026, 07:37:29 PM
Attacking the carb is what I don’t want. 1500 worth of carbs every few years doesn’t sound appealing.
Title: Re: E-85
Post by: thatdarncat on May 02, 2026, 08:25:33 PM
Thank you guys for all the responses. I haven’t been able to get on the forum for three days it wouldn’t hook me up to server. Maybe my iPad is getting old….

I had trouble getting on the forum here from my phone for a few days this past week too, might not have been your iPad. Just a FYI.
Title: Re: E-85
Post by: Jim Comet on May 03, 2026, 03:01:56 PM
I ran E85 in my 13 to 1 416fe all last summer with no issues. I would recommend getting an E85 specific carb, 8 or 10an lines (depending on hp levels) and a compatible fuel pump. I run aluminum lines front to rear on my car and use Aeroquip starlite braided lines for connections. I do run Lucas E85 conditioner in my fuel also. So far my carb and everything looks good. I do drain the E85 over the winter and flush everything with non oxy. Jim
Title: Re: E-85
Post by: Stangman on May 03, 2026, 09:51:02 PM
Hmm thanks Jim. Do you run a single or duel quad setup.
Title: Re: E-85
Post by: Jim Comet on May 03, 2026, 10:00:16 PM
Single, I had ProSystems build me a single 950cfm carb. I was not impressed with the build as the needle and seats were not what was on the spec sheet. I put in BLP 140's and upgraded everything to stainless and viton inside the carb on my own as Patrick the owner was not a great help. In the end I ended up going up 10 jet sizes from as delivered to get my 82 lamda reading on my afr to make me feel comfortable. When I dyno's the motor on race gas it made 540hp. We then switched to my E85 carb and made 530 hp with the carb as delivered. I am confident that had the O2 sensor been working on the dyno to let us no just how lean we were, we would have surpassed the race gas number. I do run pump E85. I do test it to make sure it tests at at least E80 to run it. Jim