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Thread: Dissecting the ecoboost, help me learn please

  1. #1
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    Dissecting the ecoboost, help me learn please

    So I have been slowly learning how to tune the ecoboost after learning the GM side of things. I have started playing around with my brother in-laws Focus ST. I have bought the Tuning School book for mustangs, and while a lot of the information relates to the ecoboost, there is plenty that doesn't.

    Biggest questions I have are...

    1) What controls Boost? Or what combination of things control it.
    Thing I really noticed that changed from staying at 18.5 psi (touching 19 for a split second) was the MAP gross engine torque table. Changing the values from 300 lb ft to 350 bumped up the boost to 20.5 psi. Which is great, I was wanting to get there at a slower pace and work up to it as a final boost (20-21 psi).
    Max tq.jpgtq1.JPG

    2) How can you control the throttle body better? I understand that it's best to use it to help control boost faster, but my train of thought is, instead of closing the thottle to 30%, let the wastegate do more and only close the throttle to somewhere closer to 60% maybe. I'm thinking if the throttle closes less, it will react quicker because it has less to move. But maybe I'm wrong about this. Is the wastgate maxed out at ~0.85 on my log? Can you increase it to for the point of of throttle closure?

    3) What is the true final output for spark? I'm logging a few different PIDS but can't figure out what is the final spark.

    That's the questions I have to start. Thanks.
    Nate Focus ST 1st tune plus 1 rev 1.hpt
    Plus 1 short.hpl
    Last edited by V8_Kind_Of_Guy; 02-13-2019 at 06:38 PM. Reason: I forgot to add the tune and log file...

  2. #2
    Tuner in Training fingertuning's Avatar
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    The main things to keep in mind is with the Ecoboost everything is measured in torque or load (both are the same thing essentially), so you want to control everything by torque ideally and not focus so much on a set boost level. Boost will vary in order to hit a commanded torque value, you will likely have to adjust the WGDC base table a bit eventually though.

    You can see the current spark table being used via the spark source monitor, the timing advance monitor looks to be showing the correct ignition timing that is being ran on your log.

    The throttle blade should always be the first thing used for controlling the torque, it only closes when you've hit a limit of some sort. If it's closing too much or too long for your liking that would suggest that you are likely commanding too much torque and a different limiter is being hit and causing the throttle blade to close significantly. You can monitor things like torque source and driver demand limit source to see when limits are being hit.

    On your "Plus_1_short" log you can see starting at about 2800rpm you're hitting a limiter. Driver Demand Source is showing "combustion stability" and Torque Airlimit Source is showing "5 popcorn". This would mean that your LSPI limits are being hit, and looking at your tune file I can see you have an LSPI limit of ~1.98 set in that rpm area and load desired in your log is showing 1.98 as well. That would explain why the throttle is closing through that region. You can up those limiters a bit through that region to eliminate that, something reasonable to start would be ~2.1 or ~2.2 and see how the car reacts to the change.

    As for your WGDC closed max value, you can go under Airflow --> Turbocharger and change the "Closed WG DC" from 85% 100%

    Once you figure out the limiters you are seeing and adjust them accordingly you should be able to hit the torque value you are requesting, after that is done you can start raising your torque request again.

    Eventually of course you'll want to start making some ignition timing changes but getting the basics figured out first is a good start!
    Last edited by fingertuning; 02-13-2019 at 09:56 PM.

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    Thanks for your input fingertuning, I am going to make some small adjustments as you suggested hopefully this morning.

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    Do I need to adjust both tables here for the wastegate or just 1? What do the numbers represent? I'm guessing 33513 wastegate base duty cycle is a percentage 0-100% (0-1.0)? And 45575 Closed wasegate base duty cycle is basically the same, 0-100% (0-1.0), 0.85 shown as 85%?
    WGDC.jpg

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    Tuner in Training fingertuning's Avatar
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    The Closed Base WGDC (45575) should be the table used under WOT, but I wouldn't really touch that for now, unless you're having a problem hitting your requested torque values. You're correct on how to set the values with 0-100% being 0-1.0

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    So I'm having a lot of boost drop off. How can I combat this? I have read enough to understand that it will happen with these cars but people seem like they can somewhat fix this? I also am not understanding where to adjust Desired TIP or desired MAP? The figures I see in different tables, ie Max vs Turbo airflow, don't add up. It shows 29.47psi (203 kpa). I thought maybe my baro of 12.0 psi - 29.47 might make sense but that's 17.47 psi, I'm currently showing 20 psi.

    Here's a log of a pull and tune file.
    Attached Files Attached Files

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    Tuner in Training fingertuning's Avatar
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    Quote Originally Posted by V8_Kind_Of_Guy View Post
    So I'm having a lot of boost drop off. How can I combat this? I have read enough to understand that it will happen with these cars but people seem like they can somewhat fix this? I also am not understanding where to adjust Desired TIP or desired MAP? The figures I see in different tables, ie Max vs Turbo airflow, don't add up. It shows 29.47psi (203 kpa). I thought maybe my baro of 12.0 psi - 29.47 might make sense but that's 17.47 psi, I'm currently showing 20 psi.

    Here's a log of a pull and tune file.
    I would raise those TIP max values vs airflow from 29.47 to match your overall TIP Max of ~36 . If you are seeing a higher value than what is in that table it's likely just overshooting the boost target and the throttle is closing to bring boost back down. Which looks to be the case in your log. You can see your TIP Actual is higher than the TIP Desired throughout a lot of your WOT portions. That'll probably solve most of that issue. You can also raise your Closed WGDC value from 85% to 100% this will allow more boost but I would leave it at 85% until you take a log once you made the changes to the TIP Max vs Airflow values.

    It also looks like under Torque Model --> Monitoring your IPC Map Maximum values are lower than what the stock tune has set (or at least the one I have says) in certain areas as well as higher IPC Minimum Torque values than a stock file in areas. My file could be off as it's a 2013 FoST stock file.

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    Ill go ahead and raise the Tip max values like you suggested, I was thinking of doing that, 36 sounds about right. I was also going to increase the WGDC as you suggested earlier.

    The IPC have all been increased in the .50-2.0 load by about 15% if I remember right, everything else is stock. It's crazy how it's that different from older models.

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    Well, it seems like the car took a big step backward. Things were moving forward and feeling better but now, I don't understand what's going on. The throttle is closing at 2800, which is fie, seems to be limiting the boost to about 19.5-20.5. At 4500 rpm, power drops pretty hard. I did adjust the IPC MAP max limit to limit to 65 inHg from 1.6-2.0 load so that I dont over shoot the boost limit(trying to limit boost to 20), the max gross torque is between 350-370 and the combustion stablility max map is set to 64.97.

    On the log, after 4500 rpm, MAP drops down to low 50's for some reason. I've logged more parameters to see if there is something I'm missing, but I'm stumped.

    Any help?
    Attached Files Attached Files

  10. #10
    Senior Tuner Higgs Boson's Avatar
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    you're asking for 370 ft lbs in your driver demand tables at 100% throttle

    your torque calculation tables Torque Model - General max out below that at 2.0 Engine load

    change those to show 370 (if that's really what you want to demand) at 2.0 in the correct mapped points, but what boost does it take to hit 2.0 load? is that too much boost for your turbos? if so, put 370 at a lower engine load if needed to match the max boost from your turbo.

    then make sure your limiters are one notch above that under Monitoring - Torque Max and MAP Max and Airflow - Pressure Control and Turbocharger

    better if you just open the stock tune and follow how it uses Driver Demand to Torque Calculation then uses the limiters to control it.

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    Tuner in Training fingertuning's Avatar
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    I looked through your tune real quick and I would recommend first to increase your torque limits per gear, they are still the stock values it seems.Torque_Per_Gear_Page.PNG

    I also noticed it looked like you removed the ability for the car to advance timing under Spark --> Retard --> Max Advance as well as zero'd out the the borderline timing corrections for Octane Adjustment Ratio. Is there any reason for that? You're pretty much neutering the OAR strategy which is quite a good thing to have if you end up getting excess knock.

    I would also recommend changing your requested torque values in the throttle mapping to something more reasonable, you won't be able to hit 370tq on anything other than a E30 fuel mix. I would lower the requested torque to something like 325-330tq in the throttle mapping tables to start with.
    Last edited by fingertuning; 02-24-2019 at 06:46 PM.

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    Thanks for the responses. Higgs, I get a little lost with what your saying, but i will try your suggestions maybe tomorrow.

    Finger, the torque values are higher than stock and i don't have the re-scale buttons like you either. The toque per gear is set at 378 in the engine > torque management > general for max torque 1, 2 and 3. In the transmission section, all gears are set to 738 trans > torque management > general 1st gear, 2nd etc...
    Would it be safe to re-scale the max torque under engines tab? They all stop at 3360 rpm, can you re-scale to say 6800rpm? I haven't seen anyone talk about that.

    The timing corrections that were zeroed out were a recommendation from the tuning school book for mustangs. They mentioned that they didn't like that strategy while being boosted, but then again, that was for a 5.0 mustang making several hundred more hp. They also said that knock being retarded won't be affected, it just won't allow the knock sensors to add timing until knock is heard. It sounded like a good thought process.

    I will lower the torque values as you suggested to see if that makes a difference. I also wasn't sure if maybe because I was hitting the Combustion Stability limit even though it wasn't showing up in the log. I have it set to 64.97 and the log did show it going above this. Is it possible that it is reducing the torque, he max limit is set to 221 and 64.97 inhg under combustion stabliity limit in the engine > torque management > general tab.
    torq val.jpg

  13. #13
    Tuner in Training fingertuning's Avatar
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    As for OAR I would definitely recommend keeping that strategy in place, it?s very useful. The knock response strategy is still in place of course but the dynamic timing adjustments based on fuel quality won?t work with how yours is setup currently. You?re actually losing performance with your current setup because it?s not adding the same amount of timing even the stock tune is hah.

    The combustion stability should show up in the log if that was limiting you.

    EDIT - Your tables are correct (had a brainfart) you should just need to match the non OP and OP max torque per gear.
    Last edited by fingertuning; 02-26-2019 at 08:49 PM.