3V flex fuel possible?

[Sinner]

Does anyone know if it's possible or if there's a system being developed for us 3V guys to run flex fuel?

I'm going to run e85 in the near future but I would love the versatility of flex fuel.

 

[dysan]

I think you would need an aftermarket ECU to do it. I think the megasquirt system can do it. Never looked at the BS3 or other stupid expensive systems but I wouldn't be suprised if they could do it also.

 

[Department Of Boost]

Some of the F-150 ECU's have Flex Fuel built in. Could that be used?

 

[JeremyH]

Does swapping tunes at the pump while it fills up count? lol

 

[Sinner]

Some of the F-150 ECU's have Flex Fuel built in. Could that be used?

I don't know... You're the person that even caused me to think if this. lol

 

[Sinner]

What I like about flex fuel is that it eliminates the need to check the E85 at each fill up..... I'm lazy.

 

[s8v4o]

Some of the F-150 ECU's have Flex Fuel built in. Could that be used?

I've often wondered the same thing. It seems within reason that a F150 PCM and wiring harness swap could work. Do the F150's have a flex fuel sensor like the GM's do? If not I wonder how it make it's calculations? I bet Lito would have some good input on this subject.

 

[Pentalab]

So what happens when u have a 1/2 tank of gas...and half a tank of E85 ? Do you end up with E40?

 

[slackinoff]

So what happens when u have a 1/2 tank of gas...and half a tank of E85 ? Do you end up with E40?

I bet many can do this,... but the one aftermarket ecu I know a tiny bit about can detect that, and scale the tune accordingly.
It has a sensor that the fuel flows through..... I am not sure how that sensor is determining the ethanol content.

 

[702GT]

I think even if you could swap computers, harnesses, and sensors to make a flex fuel mustang, I don't think it would be worth it. The tune optimization isn't there for performance or economy. I also think it could be dangerous if it was optimized. I usually run 2 full tanks of e85 through the system before I get heavy on the pedal, to make sure all the 91 is out. The ammount of spark advance I run on my e85 tune for both open and closed loop is hot compared to my 91 tune. Not sure what the ignition stability would be like with mixed fuels on either tune. I know the first tank of e85 runs like dogshit for a while. And vice versa when switching back to 91.

Flex fuel kind of sucks as it is currently. My buddy has a flex fuel F150 and he says his fuel economy tanks by 30-40%. My fuel economy only suffers about a 10-15% loss, which is more than acceptable considering the gains.

I suppose if you had a flex fuel setup and could optimize both sides of the tune, it might be the way to go. I guess only a tuner would know if it can be done. One of those have your cake and eat it too, situations.

 

[JeremyH]

Leaving a little 91 just makes the car a little richer/safer. E85 is 85% ethanol and 15% 80ish octane gasoline. When running a e85 tune if you get e80 or e70 the car runs richer from more gasoline, more ethanol would make it leaner. I wait till I'm under 1/8 tank, load the tune as I fill with e85 and go. It stumbles at idle for a little bit as the gasoline gets out of the line, then good to go.

 

[BruceH]

Does anyone know if it's possible or if there's a system being developed for us 3V guys to run flex fuel?

I'm going to run e85 in the near future but I would love the versatility of flex fuel.

Don't think so, not for wot open loop anyway. A 5.0 with the wideband should be able to do it based on the wideband feedback. Haven't seen the 5.0 tune to be sure about it.

 

[JeremyH]

Yeah the wideband front 02's is what allows the 11+ to do it.

 

[BruceH]

Yeah the wideband front 02's is what allows the 11+ to do it.

I have both my gas and e85 tunes setup to run either fuel but it's just for emergency purposes. The minute it went into open loop while running gas with the e85 tune would be trouble.

If I was ever stranded on the e85 tune I'd still be able to limp home on gasoline. The motor would be relying on input from fuel trims for fuel metering. All it really takes is adjusting what's allowed for fuel trims before going into limp mode.

It's just too bad we can't run widebands for the ecu.

 

[Shok]

Leaving a little 91 just makes the car a little richer/safer. E85 is 85% ethanol and 15% 80ish octane gasoline. When running a e85 tune if you get e80 or e70 the car runs richer from more gasoline, more ethanol would make it leaner. I wait till I'm under 1/8 tank, load the tune as I fill with e85 and go. It stumbles at idle for a little bit as the gasoline gets out of the line, then good to go.

Did you change any part of the fuel system or anything else to run e85 or is only a tune needed?

 

[JeremyH]

Did you change any part of the fuel system or anything else to run e85 or is only a tune needed?

I run a return system and have two tunes.

 

[Sinner]

I run a return system and have two tunes.

That's what I'm going to do.

 

[BruceH]

Did you change any part of the fuel system or anything else to run e85 or is only a tune needed?

It can be done with just a tune. Fuel requirements will depend on where you are mod wise. The stock lines, injectors, pump, etc. work just fine with ethanol if that's where you are going with the question.

 

[weather man]

COBB hooked up the Subaru guys. Maybe they will hook up the ecoboost dudes!

http://www.cobbtuning.com/subaru-flex-fuel-is-here/

 

[Sactown]

best solution is having 2 different tunes