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Discussion Starter #1
Morning All,

Quick question for your guys. I am over in Ireland, we do not have E85 available here on pump. The fuel available in the pumps here is 95. I do not know if that is RON or Octane.

Any car I ever had was always just setup / mapped on pump fuel.

My question here is if I have a flex fuel setup with my ECU (EcuMasters Black) can the car be ran / mapped for a flex fuel setup?
E.g If I am driving the car normally can I use regular pump fuel and the ecu will know this and adjust accordingly. Then if I put in a higher octane fuel say VP will the ecu adjust for the higher octane fuel etc

Hope what I am saying is making sence. Basically I would like to run the car in normal environments on pump fuel. If I am ever taking the car out for a ''spirited'' drive I can fill it up with VP fuel and it will work accordingly with the higher octane = more power etc

Thanks
 

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flex fuel is the ability to run on e85 ethanol or petro gasoline fuel OR any ratio between 10%ethanol (petrol gas) through 85 % ethanol (e85 summer blend)

because you can alternate fill ups / have drastically different amounts of alcohol in the fuel "flex fuel" cars use a special flex fuel sensor to determine how much ethanol is present in the fuel

in that scenario you would have a straight up gasoline tune, and also a straight up e85 (aka 85% ethanol alc.) tune. when your tank has say 60% ethanol in it, the sensor reads that and adjusts to an appropriate tune ...that is a blend between the 2 tunes (gas/alc tunes)

now with a stand alone you can store multiple tunes, and potentially toggle between them with a dip switch. this is totally different than a flex fuel sensor reading the fuel and adjusting the tune automatically.

with 2 entirely different tunes (gas tunes for diff octane) you could have a conservative tune for 95 octane

and then a tune that is more aggressive (more boost, more timing, leaner etc) for the high octane fuel


there is not a sensor I know of that can determine octane in the fuel. the engine knock sensor can to a degree because higher octane fuel will knock less and allow that type of system to run more advanced timing
 

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Dempsey, from my understanding, your 95 is RON, just like it is here in NZ. So that is the equivalent of 91 in the USA.

We have 98 RON here at certain fuel stations, and that is the equivalent of 93 in the USA.
 

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As I understand a flex fuel sensor actually measures gasoline content and subtracts this from 100% to find the ethanol content, but can't decipher octane level. I don't have experience with the ECUmasters computers so I can only draw from my computer (Infinity), but it could be possible to configure a mode switch input to achieve switching between pump and race gas settings based on the voltage input the computer sees.

For instance if you created a boost target table with Modeswitch Voltage on the X axis you can then manually raise or lower the boost target setting based on the fuel you have in the car by moving the switch, and adjust timing if desired by a trim table as well to adjust from your main ignition table. As a quick example, if you desire the '1' position showing 0.1v to be used for pump gas at 18psi, '2' at 0.6v and '3' at 1.3v to be conservative blends of increasing octane and '4' 1.9v to be full race gas at 30psi your boost target table could look something like:

18psi21psi23psi30psi
0.1v0.6v1.3v1.9v

Again this is based purely on the little experience I have with my Infinity so far, and I'm not sure if the ECUMasters Black will have the same functionality or a better way to do this.
 

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Discussion Starter #5
Thanks for taking the time to answer the above. Will speak to engine tuner when it comes time for mapping
 
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