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Turbo98

How do Various Blends of E85 Affect Performance?

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I would think the difference in E85 and E70 would be handled by the ecu at least in the closed loop?

 

 

Any thoughts on this by some of the tuners out there?

 

 

 

This is what I am wondering also.  Like in BoostedGTP's car, is the ECU trimming the fuel down by 8% or is he doing it manually when switching to the E70.  I would think that the 02 sensors are fine tuning it to bring the A/F to the same level.

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The car's own computer already has the ability to fine tune up to a factory set range. Flextek just adjusts the width of the pulse alittle higher so the car's own computer can fine tune at that high level using the O2 sensor.

 

G setting is off - up to around 40-50% on most cars

 

A setting is on - down to 50-60% alcohol.

 

So I would not be supprised to see a tuned vehicle still have that + or - range after it is tuned to E85.  I am not a tuner, but I do know factory vehicles have the abillity to adjust for seasonal blends and/or E10.  They use the O2 sensor to fine tune A/F.

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You guys are talking about the computer fine tuning. On my 1992 Toyota 4x4 with 22RE engine the Split Second mixture meter dithers rich/lean constantly, so is it fine tuned? According to the literature that came with it, dithering means the O2 sensor is working properly.

Marty

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  You mentioned using a sensor to detect the grade of fuel you're using.

 

    If you have a nearby junkyard , check for an inline sensor that was used

  to measure fuel quality in the early days of FFVs.  Nowadays they just

  use the O2 sensor to adjust.  I think Ford stopped using these in 2001,

  so you'll have to find a junked FFV Ranger pickup or Taurus from that era.

  Or maybe just search the manual for either of these and by the part outright...

  There are a couple places to find VIN #s of FFV from years past. AFDC on

  doe sections will have it.. So will NEVC.   

 

      What you're measuring is fuel conductivity. Not sure you'll be able to do

    much once you know what the number is , perhaps you're using this + knock

    sensor to adjust boost.. So you have twin turbos, you say ......

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  You mentioned using a sensor to detect the grade of fuel you're using.

 

    If you have a nearby junkyard , check for an inline sensor that was used

  to measure fuel quality in the early days of FFVs.  Nowadays they just

  use the O2 sensor to adjust.  I think Ford stopped using these in 2001,

  so you'll have to find a junked FFV Ranger pickup or Taurus from that era.

  Or maybe just search the manual for either of these and by the part outright...

  There are a couple places to find VIN #s of FFV from years past. AFDC on

  doe sections will have it.. So will NEVC.   

 

      What you're measuring is fuel conductivity. Not sure you'll be able to do

    much once you know what the number is , perhaps you're using this + knock

    sensor to adjust boost.. So you have twin turbos, you say ......

That's the challenge.  Like you said....  There has to be a way to get that signal from the sensor to be used by the computer.  I have thought about the knock sensor also.  I am not real familiar with how the knock sensor works.  I know it adds like 2 volts when it detects a certain frequency of shock wave. 

So, without some software to manipulate the signal and get that info into the ECU to use, it will be difficult to use the sensor on a non-ffv car.

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2 volts?  Some Op-Amps or logic gates can settle those debates for you.

 

The fuel measurement may inolve a little more. I remember seeing an

article on the IEEE website about how these were designed. You may

need to go back a few years, tho.  The other method would be to look

in the schematic of a Taurus or Ranger FFV, and duplicate what they

used ( it may be a black box). I'll bet we're talking about signals less than

5 volts, tho, which lend themselves nicely to a little bit flipping with

simple logic gates.... sounds like  fun..you may even be able to drive an

LED display to show the actual number  ( 70 thru 85%). 

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This is what I am wondering also.  Like in BoostedGTP's car, is the ECU trimming the fuel down by 8% or is he doing it manually when switching to the E70.  I would think that the 02 sensors are fine tuning it to bring the A/F to the same level.

 

The PCM takes care of all the changes by itself, once I get a tune done it's good to go all year around.  You are correct, the PCM uses the o2 sensor for the fuel trims.

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This is what I am wondering also.  Like in BoostedGTP's car, is the ECU trimming the fuel down by 8% or is he doing it manually when switching to the E70.  I would think that the 02 sensors are fine tuning it to bring the A/F to the same level.

 

The PCM takes care of all the changes by itself, once I get a tune done it's good to go all year around.  You are correct, the PCM uses the o2 sensor for the fuel trims.

Sounds good.  How much boost are you running?

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