Ms3 basic trackspeed flex sensor
#2
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Flex input is pin 26 on the DB37. If I recall, the setting needs to be enabled in the software before the ethanol content gauge will start working.
Last edited by Savington; 11-07-2016 at 01:30 AM.
#3
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Got the wire soldered to pin 26. Make sure you look at the sensor itself and check the wire locations for sensor output, ground, and vcc. Very small lettering on the flex sensor itself. Might need a magnifying glass. My power, sensor, and Vcc were in different than those on the megasquirt page on flex fuel. Working great with outputs for ethanol content and temp. Thanks.
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From https://www.miataturbo.net/megasquir...2/#post1340112
Here's how I would set up a fresh MS3 flex fuel install.
1. Dial everything on gasoline and save your tune.
2. Install the flex fuel sensor and set Baseline Ethanol% to the value you get with "100% gas" (in CA this was ~8% for me)
3. Turn on flex fuel, but leave all the alternate maps off. This just leaves the global blend, but doesn't allow blending between VE1/VE3 (or Spark 1/Spark3, etc)
4. Drain the tank and fill it with E85. Tune the spark/fuel, AFR target, ASE/WUE/Accel maps, and all the other maps that have switching available in the software. Tuning all these maps on VE1 will let you use Autotune like you normally would. Put a few tanks of raw E85 through the car to get the content up as high as you would ever see it, and make sure the tune is dialed in.
5. Load the set of E85 maps into the alternate map positions, load your gas maps from step 1 into the primary positions, and turn table switching on. Set the flex blend curve so that the ECU switches over to the alternate maps by 80%EC
6. At this point, you're about 95% of the way there. The only setting left to dial in is the flex blending map, and that will happen by trial and error with varying levels of ethanol content in the fuel.
1. Dial everything on gasoline and save your tune.
2. Install the flex fuel sensor and set Baseline Ethanol% to the value you get with "100% gas" (in CA this was ~8% for me)
3. Turn on flex fuel, but leave all the alternate maps off. This just leaves the global blend, but doesn't allow blending between VE1/VE3 (or Spark 1/Spark3, etc)
4. Drain the tank and fill it with E85. Tune the spark/fuel, AFR target, ASE/WUE/Accel maps, and all the other maps that have switching available in the software. Tuning all these maps on VE1 will let you use Autotune like you normally would. Put a few tanks of raw E85 through the car to get the content up as high as you would ever see it, and make sure the tune is dialed in.
5. Load the set of E85 maps into the alternate map positions, load your gas maps from step 1 into the primary positions, and turn table switching on. Set the flex blend curve so that the ECU switches over to the alternate maps by 80%EC
6. At this point, you're about 95% of the way there. The only setting left to dial in is the flex blending map, and that will happen by trial and error with varying levels of ethanol content in the fuel.
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As Albert said, you really need to start with a near-perfect gas VE1 table before you start tuning on E85. Any future tweaks you do on the gas map will change your E85 tune as well, which is what you want to avoid.
#9
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In the process of tuning e85 on auto tune now. Runs nice and usually starts on one key turn. I was planning on moving the e85 table to ve3 position and using my already tuned 91 octane to take ve1 space. Then turn sensor on and have it blend between the two tables depending on what sensor indicates. Thanks for your time.
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Flex fuel has a global fueling curve based on ethanol %. It's a more specific mode than just table blending. If you flip on FF with an E85 tune copied to VE3, you'll start running way rich because VE3 will be tuned without the global modifier. Of course, these problems are fixable, but if you don't have E85 yet, follow this instruction before you tune your E85 map:
It just makes it easier for you to move through the steps.
Originally Posted by Savington
3. Turn on flex fuel, but leave all the alternate maps off. This just leaves the global blend, but doesn't allow blending between VE1/VE3 (or Spark 1/Spark3, etc)
#12
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OK will redo my e85 tune. I have a couple of questions. On my tuned 91 octane map I have adjusted my ignition timing by +10 degrees all alround. When I use that table to start to get a tuned e85 table will the flex sensor add timing to it? Will it adjust to how much advance I input in the flex fuel section? Is +13 advance a good number to put in there? Thanks for all your invaluable help guys.
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The flex fueling curve does not intrinsically have to add timing. You want to add spark through actual table blending.
People have E85 timing maps (Google with site:miataturbo.net). Reading those threads would be a good place to start. Although it's harder to break something with E85, do 10x more reading than copying to play it safe.
On the other hand, if you use the "forum dyno" to help on a gas map, you may break your car because you're on 91.
Edit: there's no reason why you can't use the linear timing addition from ethanol percentage, which is what it sounds like you're asking. I didn't, and if you do you won't be able to copy e85 spark maps.
People have E85 timing maps (Google with site:miataturbo.net). Reading those threads would be a good place to start. Although it's harder to break something with E85, do 10x more reading than copying to play it safe.
On the other hand, if you use the "forum dyno" to help on a gas map, you may break your car because you're on 91.
Edit: there's no reason why you can't use the linear timing addition from ethanol percentage, which is what it sounds like you're asking. I didn't, and if you do you won't be able to copy e85 spark maps.
Last edited by afm; 11-08-2016 at 11:10 AM.
#18
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What dyno testing did you do to determine that 15 degrees was the appropriate amount of advance? (hint: this is a trick question)
On my gas ignition map, I get ~15mpg on E85 (~21mpg on gas).
I would encourage you to re-evaluate your tuning strategy on E85. Start over, basically, and follow the instructions I posted above.
On my gas ignition map, I get ~15mpg on E85 (~21mpg on gas).
I would encourage you to re-evaluate your tuning strategy on E85. Start over, basically, and follow the instructions I posted above.
#19
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At the shop in Livermore, CA getting a tune with Richard. I just finished the m45 SC install on my 2000 NB. A few weeks ago I completed my E85 sensor. We are tuning a MS3 Basic from Trackspeed. Will post up results from dyno. Will be on a dynopack. Stock 1.8, stock rad, stock injectors, stock fuel pump. Lets see how we turn up
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