e85 with colder plugs for Knock Retard? and its 105 octane level

[chargedvx6]

How do you go flex fuel with the Ecotec ECU though? I know it's essentially an addon with the later LS and Alloytec based ECUs.

Dual mapping has been in use for ages for LPG. Just re assign the LPG sector for E85 with some custom defs in a nut shell

 

[_R_J_K_]

Dual mapping has been in use for ages for LPG. Just re assign the LPG sector for E85 with some custom defs in a nut shell

Do you know of a thread that shows how this is done (even for LPG)?

Would I be right in saying that you could only run pump fuel and e85, no in betweens? How does the flex component fit in?

 

[Mike Litherous]

You can alter the fuel pressure to run e85 considering the fuel pump is up to the task. This is what a friend of mine done with a 14:1 comp BMW to get it to run. There is no substitute for proper tuning as the timing will be far from optimised.

I'm building a 8.5:1 comp BMW m3 with 18psi boost. I'm going to use a flex fuel sensor so I can run any mix of e85 and pump Ron 98. I'm running a haltech ecu which can handle all the data. Basically the flex fuel sensor calculates the punt if ethanol present and interpolates the mapping for the blended fuel mix.

I'm going to use prodomatly e85 as it will run cooler and can optimise timing etc. To run e85 only has limitations especially iif doing a country trip

 

[Jxfwsf]

Do you know of a thread that shows how this is done (even for LPG)?

The factory LPG tunes have different ignition maps and shuts off the injectors.

I'd be interested to see how to turn the injectors back on and use a different fuel map.