Configuring your tune for multiple Ethanol percentages via map switching

Discussion in 'Fiesta ST EcoBoost™ Tuning' started by razorlab, Dec 20, 2014.

  1. razorlab

    razorlab Active Member

    This will outline how to set up your current (our future) tune for correctly using different ethanol percentages.

    First order of business is to setup and install your Ethanol percentage sensor hardware as I outline in this thread.

    While using an actual ethanol sensor as linked above is currently the most accurate way to do this, you can also loosely figure out Ethanol percentage by using the analog math way with this handy chart below:

    [​IMG]

    I highly recommend using hardware as you will know exactly what percentage of Ethanol is currently in the car instead of doing math and guessing.

    Now, if you did either of the above, you have an Ethanol mixture in your Fiesta ST. The ECU in the Fiesta ST is very powerful and sophisticated and it will be able to handle about up to 30% Ethanol without any software changes by using fuel trims to compensate. HOWEVER, it's better to set some parameters in the ECU so that the fuel trims don't have to work as hard to compensate. This will make the car drive smoother and have smoother power delivery, better gas mileage and better peace of mind knowing the ECU is changed to run correctly.

    In order to do this, you *must* have a COBB Accessport and also you *must* have COBB Accesstuner Race software to make any changes to your tuning.

    Below I will outline how to make some changes via Accesstuner Race. These instructions are how to setup the BASE LEVEL of software changes in order to have the fueling system setup for various levels of Ethanol percentages. Again, this is the BASE LEVEL. There are more advanced software changes you can make that will allow you to FULLY take advantage of the Ethanol and make more power. I will outline these at a high level after showing how to set up the base level.

    Setting up Accesstuner with base level fueling table changes:

    1. Open COBB Accesstuner software
    2. Load your current tune. I am using the COBB Stage 3 91 octane tune for this example.
    3. Once you open your current tune in Accesstuner, the screen should look like this. Locate the "Switchable Maps" folder in the table list on the left:

    [​IMG]

    4. Expand that folder by double clicking on it. Then expand the "Configuration" folder by double clicking on it. It will look like the screenshot below:

    [​IMG]

    5. Select the "Active Map Slots" table within that folder. The table value will be on the right in the black space and you will change the number in this table by either hitting "E" on your keyboard to edit the table or the "+" or "-" key to increment the number up or down. You want to change this value to 4 as shown in the screenshot below. This enables 4 switchable maps. The reason we want 4 switchable maps is for, E10 (normal gasoline), E20 (20% Ethanol) E30, (30%) and E40 (40%).

    [​IMG]

    6. Next, select the "Configure 5-way Desired Fuel Target (Power Demand) table and set this value to 0 to disable it. This will make the ECU run one Fuel Target table for ALL of the switchable maps. Remember this is for setting up basic Ethanol switching. More advanced tuning will enable this and will allow separate Full Target tuning for each switchable map slot. For now, set this to 0 as show in the screenshot below:

    [​IMG]

    7. Now select the "Configure 5-way Fuel Scalar Stoich. Setpoint" table and change the value to 1 to enable it. This allows us to set the correct fueling scaling for each Ethanol percentage mixture in each map slot. After setting this to 1, it should look like the screenshot below:

    [​IMG]

    8. Next you want to go down the Configuration list and make sure all the other Configurations are set to 0 and disabled. I have no screenshot for this but it is pretty straightforward. After you have completed this, pat yourself on the back because you are now done with the configuration portion of this. [​IMG]

    9. Under the "Switchable Maps" folder, located the "Switchable Map 1" folder and double click to expand it. Next locate the "Fuel Scalar Stoich. Setpoint" table and select it. This is your first switchable map and for this example, it will be used for regular gasoline . If you are using gasoline that already has 10% Ethanol in it (most gas in America) then you want to make sure the value in this table is set to 14.08, as shown in the screenshot below. If you are using gasoline that DOES NOT have Ethanol already in it, you can set this value to 14.64.

    [​IMG]

    10. Locate the next switchable map folder, named "Switchable Map 2" and double click to expand it. You are going to be doing the same thing as outlined in step 9 above. Select the "Fuel Scalar Stoich. Setpoint" table and change the value in this to be 13.51. This Switchable Map is for E20, or 20% Ethanol. It should look like the screenshot below:

    [​IMG]

    11. Now locate the "Switchable Map 3" folder, double click on it to expand and select the "Fuel Scalar Stoich. Setpoint" table and change the value in this to be 12.95. This Switchable Map is for E30, or 30% Ethanol. It should look like the screenshot below:

    [​IMG]

    12. Now locate the "Switchable Map 4" folder, double click on it to expand and select the "Fuel Scalar Stoich. Setpoint" table and change the value in this to be 12.38. This Switchable Map is for E40, or 40% Ethanol. It should look like the screenshot below:

    [​IMG]

    13. Save this file, load it up on your Accessport and flash this file to the ECU using the Accessport. Congratulations, you are now setup for up to E40 Ethanol mixtures. Depending on your current mixture in the car, you can switch to the appropriate map and since we mapped each switchable map number to an Ethanol percentage, it will be easy to know which map to switch to as the numbers on the tach of the car (during map switching) correspond to each Ethanol percentage. Example: 1,000rpm = Gasoline, 2,000rpm = E20, 3,000rpm = E30, 4,000rpm = E40.

    You're done with the basic setup!

    Now, let's take this one step further and take some more advantage of those Ethanol mixtures to make even more power! The following will show you how to setup the ECU to add additional ignition timing for each switchable map.

    *DO THIS AT YOUR OWN RISK*. Again, this is the base level of additional changes for Ethanol and for this example I am using the COBB Stage mapping for an example. It runs a fairly soft ignition timing curve in it's tuning and adding some additional ignition timing is fairly safe. If you are custom tuned by somebody else, discuss this with your tuner first!

    1. Locate the "Switchable Maps" folder in Accesstuner. Double click to expand and then locate the "Configure 5-way Ignition Timing Offset (Base) table. Change the value in this table to be 1 to enable it, as shown in the screenshot below:

    [​IMG]

    2. Locate the "Configure 5-way Ignition Timing Offset Strategy" table and change the value to be 0, to enable 1D table strategy (instead of the more advanced 3D strategy). Your screen should look like the screenshot below:

    [​IMG]

    3. Now, for EACH OF YOUR SWITCHABLE MAPS folders, locate the "Ignition Timing Offset (Global) 1D Load Min." tables and set the value in this table to be 1.500, as shown in the screenshot below. Do this for each switchable maps 1-4. What this does is set the ECU to only use our additional ignition timing once the car is ABOVE 1.500 load, or basically once the car is in boost at WOT. That way when you are just driving normal, the additional ignition timing is not used. Again, this is base tuning for Ethanol. More advanced tuning can change this as well and I might do a write up about that in the future.

    [​IMG]

    4. Now, for EACH OF YOUR SWITCHABLE MAPS folders, locate the "Ignition Timing Offset (Global) 1D" tables and set this to how much ignition timing you want to add. My suggestion would be to change this value to 1 for your E20 switchable map, set it to 2 for your E30 switchable map and set it to 3 for your E40 switchable map. The screenshot below shows a value of 1 for Switchable Map 2, which would be E20. For your Switchable Map 1, which would be normal gasoline, this value should be 0.

    [​IMG]

    Be very careful of adding too much timing. My suggestions work fine for the normal COBB stages for each percentage of Ethanol. Be sure to load this file to your accessport and flash to the car to take advantage of these changes.

    More to come!
     
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  3. Cesso

    Cesso Member

    Awesome guide Razor! Is there an upper limit to how much ethanol you can mix in? I read that you did an E45 mixture with good results, given what you have found out is running straight E85 possible?
     
  4. razorlab

    razorlab Active Member

    There isn't any power to be gained going past E45 with the stock turbo. You can reach MBT no problem. All you would be doing is decreasing mileage with more Ethanol.
     
  5. Cesso

    Cesso Member

    I didn't mean with the intention of extracting more power, just the simplicity of filling up on E85 without mixing in gasoline. I can get E85 incredibly cheap, gas mileage isn't really a concern at all. I was just curious if there was any limiting factor preventing its use in these cars.
     
  6. razorlab

    razorlab Active Member

    To be honest my plan was to see if the FiST could take E85 with the stock fuel system but when I found no gains after E45 I stopped at around E60 and then went back to E30-E40 on fill ups. I have no idea if the car will support full E85. I know the MazdaSpeed3 guys have had issues with their HPFP on higher ethanol mixtures.
     
  7. razorlab

    razorlab Active Member

    Wanted to add a point of education since the same person that copied my information around the Ethanol gauge on another forum is stating that when the Ethanol pump at the station has a sticker that says "70% Minimum Ethanol", he thinks it means it's only E70, not E85.

    Here are the facts. Every E85 pump, by law needs to have that sticker on it. It is not necessarily the Ethanol percentage you will get. It is stating that 70% is the MINIMUM ETHANOL REQUIRED BY LAW. It doesn't matter if the pump dispenses E85, E80, etc, it will have that sticker on it.

    Every pump here in Northern California has that sticker and it's E80-E85 every time.

    Just clearing up some misinformation here. I've been using Ethanol in all my cars for over seven years now. I've seen it all so far.
     
  8. ryst

    ryst Active Member

    Razor. So lets say I have an E40 tune that a really good tuner made for me ;) , and I want to configure switching backwards from the timing on the E40 tune for different % of ethanol. Will the 1D timing change per table be enough of a change for the E40 tables that you wrote, or would I need to modify the rest of the tables (not just WOT).

    (also E85 is under $1 near me, woo)
     
    Last edited: Dec 23, 2014
  9. WScottCross

    WScottCross Well-Known Member

    Seriously? I see why you guys want to run it. It's only slightly cheaper than 87 octane E10 here and the milage hit actually makes it more expensive to run than E10.
     
  10. ryst

    ryst Active Member

    Yeah it's pretty crazy. The weird thing is some places are like $1.70+ but some are $0.99, big gaps in pricing.
     
  11. BlackBird

    BlackBird Active Member Staff Member

    Scott, where are you getting your ethanol fuel? I didn't think there were any stations in CT selling it at-pump.
     
  12. WScottCross

    WScottCross Well-Known Member

    Only one station that I can find in CT. It's a Henny Penny in Waterford on Rt85. 5 gallons of E85 with the rest of the tank being E10 ends up at E40 overall. Makes it pretty easy to mix at the pump. It gets tricky if you have a partial tank of E40 already. I try to run that tank down pretty low before refilling if I already have E40 in the tank and then put in a little less than 5 gallons of E85.
     
    BlackBird likes this.
  13. koozy

    koozy Active Member

    Hey razorlab, thanks for putting out this info. Along with the hardware kit and this info I was able to set myself up with 5 ethanol maps. 4 based off your info here with some tweaking and 1 pseudo eco map for low boost when it's wet out, because traction is an issue now, LOL. Anyways, thanks man. :thumbsup:
     
  14. koozy

    koozy Active Member

    Ok, here are my virtual dyno results for Cobb stage 0 base map and Cobb Stage 3 91 octane base map configured for E40, as such focus on the deltas and not so much the peak numbers. Keep in mind I have an intercooler and downpipe, but basically this is roughly what one can expect by following the guide outline by razorlab above. No tweaking or tuning of the maps have been done yet. I'm hoping razorlab will someday soon continue with this guide and his next series of tuning the FiST.

    Current Mods: Airtec Intercooler, Cobb Downpipe, and of course the Accessport.

    Stage 0
    184whp/213wtq

    Stage 3 base w/E40
    207whp/288wtq

    Gains
    +23whp/+75wtq

    [​IMG]
     

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