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E85 sensor

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Hi Steve.

You are correct, the E85 sensor has now been included.  When you connect the 'Raw' signal to a digital input. The following information can now be used as an axis in a Fuel Adjustment table.

· E85 % Ethanol - this is a measure of the percentage of ethanol within the measured fuel.
· E85 Temperature - this is a measure of the fuel temperature.

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Bump of an old thread, the search function worked! I'm looking to do this, run an E85 sensor and do a 4D overlay (fuel and ignition) so i can run anywhere from 0% ethanol to 85% ethanol without any driver input/switching required. I have come across this product: http://www.zeitronix.com/Products/ECA/ECA.shtml Is there any other Ethanol sensors that Link recommends? this is quite expensive at $359USD plus postage (retail). And can we confirm (again) that the raw signal can be used with the required addition box to convert to 0-5v signal. Cheers, Mike

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Just to bump this one up again, I've so far seen people only mentioning a single overlay table for ethanol content correction (presumably each for ignition and fuel) - what axis configuration do you guys use, or envisage for a flexifuel tune setup?

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OK, cheers... thats what I was wondering - so the adjustments are basically just to scale the entire ignition and fuel maps to match the ethanol blend? 

So hypothetically speaking (just plucking numbers off the top of my head) if you tuned the base map on straight 98, then set up an overlay for eth blends you could end up with a +35% fuel trim to the entire fuel table if E85 is in the tank, and the same kind of thing with ignition?   

The reason I ask are for 'curly' situations,  such as where the shape of the base ignition tables may be influenced by the knock limitation of petrol, while on E85 the same car may be able to be mapped to MBT under the same conditions.  Makes sense if there are compromises to make one size fit all, but I like to ask just in case this kind of thing has been covered and I've missed it :)

Cheers

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If there were big differences then you could go to dual maps with an over lay.

This would allow a manual switch of the main tables and still have a correction for variances in ethanol

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Hi, I'm trying to nut out a way of making boost control (switch tables and, or at least MAP limits) based on ethanol content.   I had looked at switching MAP limits using the virtual aux configured to switch if ethanol percentage is over a particular threshold, however ethanol % isn't in the drop down list (could this be a wishlist item?). 

The ethanol %age can of course be used as an axis in the boost target table, but it'd be nice to have a tailored WG duty cycle table to suit as having the same WG duty table for both a 18psi target (straight petrol) and a 30psi target (for 30%+ ethanol) may not be optimal... and of course have the MAP limit set to suit.

Any input would be appreciated :)


Dan

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have had full flex-fuel setup running on my GTR for 1 year, check SAU and search 'flex fuel' - you'll find my write up :)

Zeitronix sensor and G4 plug-in - for those asking about sensors, they're just GM units... you could get one from a wrecker in the states for $50 or there-abouts, but i wasn't game to get a 2nd hand part when being guinea pig with this all.

System works great though, never have to worry about what i fill up with now :)

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I'm well familiar with that thread ;)  Good to hear the car is trucking on nicely with it, sensor been reliable?

So does anyone have any thoughts or advice on map limit switching based on ethanol content?  As a fail safe it'd be nice to have the ECU cut the fun if someone tries to run a boost level only intended for higher ethanol contents when there is a low ethanol mix going through the rail....

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You can have a 2nd map limit table and you could choose to have this spanned on ethanol content.

Much the same for the boost target you can set the target table to be spanned based on % ethanol.

So for less ethanol you have less boost.

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Cheers - I will check out setting ethanol content as an axis tonight, for some reason I thought I had tried that and was either not able to change the axis setup setup - or couldn't select ethanol % as an option though could have missed that.

I did see I could span the boost target table based on ethanol content, though I tend to try and get the wastegate duty cycle table optimised for the boost target I am aiming for - and if I span target based on ethanol content, have the wastegate table optimised for 18psi (for pump gas) and have E85 in the tank, and have the boost target for E85 set as 30psi then the closed loop boost control could have fun with that. 

Thanks for the input, I thought I'd check before I set too much - will try it out this weekend.

Dan

 

 

 

 

 

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Hi Daniel,

You are correct, you can not select ethanol content as a parameter for the MAP limit table. You could limit your RPM using a GP limit table, using ethanol content and MAP as the axis.

Cheers,

Scott

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Good morning Daniel,

I'm not sure on the reason for the 60% limit, we will look at getting this increased. In the mean time a solution for you would be to use the 'Dual Fuel Table' function in overlay mode. With this table you can make trims from -100% to +150%.

Cheers,

Scott

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Hi Scott,

Thanks for that - I had already got it all running fine, I rescaled the base fuel map to suit having adjustment required in the 4d table for 40-50% ethanol and then negative trimmed the same amount for 0% and adjusted the rest of the table to suit... it worked out fine, but wasn't pretty and would obviously be nicer to just have bigger trim limits :)

Cheers,

Dan

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