Flexfuel and MS3

[Dudeland]

Is anybody using the flex fuel capability on their MS3 conversion?  I just want to know if it is worth it. 

 

[irdave]

Do you need bigger injectors to make that work properly?  And some sensor to measure the amount of ethanol?  Or do you just tell it what you have?

[jimk]

Dave,  Here is some info..

https://www.haltech.com/how-flex-fuel-control-works/

 

i think a sensor with a Haltech is only necessary if E85 is used from time to time.  If there is a consistent use of a fixed percentage of ethanol in the fuel, select the type of fuel on the fuel tab in setup and enter the percentage of ethanol.  Then if there is a change to another fuel, enter the fuel info and that's it, no returning necessary.

On the issue of injector size, E85 needs bigger injectors, but the 10% stuff is not noticed.  Dave, I am waiting to see how your stock injectors duty ends up.  Will be ok for our altitude, but at sea level maybe.  To change later is a slam dunk, and no retune needed.  See the Haltech support forum for that question and results from a change on today's posts.

Edited August 27, 2019 by jimk
Additional info

[Dudeland]

Super cool, thanks.  I am interested in E85 simply because I can potentially lower the cyl head temps by running E85 ( or so the internet says) and boost octane.  Which for a $30 sensor and $100 in  AN lines, I could take advantage of this functionality.

 

In addition Halltech did a faq on youtube.   One of the questions was around using the fuel sensor so you can have a specific tune for the actual fuel in your tank.   Kinda cool. 

 

Still unforeseeable months away from doing anything.  The next three months are crazy for me.  

 

 

[2002iii]

With a proper tune e85 can run cooler and get you more horsepower. But you need the right tuner. I would suggest you find a shop that has done e85 tunes and ask them what they recommend.

[xr4tic]

The downside of E85 is that it uses 50% more than regular fuel, so your injectors have to be bigger and your fuel tank capacity essentially shrinks.  The stock 12 gallon tank would essentially be 8 gallons.

 

You would also have to tune the car twice, once for each gas type, if you plan on switching back and forth.

 

I would love to see an E85 vs gas dyno comparison though.

 

What compression ratio do you have and what is your boost PSI target?