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Thread: Borderline Spark VS MPT Spark

  1. #21
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    ... Glad you mentioned polling speed because maybe u need to turn it up. I'll look into that

  2. #22
    Advanced Tuner AKDMB's Avatar
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    Quote Originally Posted by ridenrunwv View Post
    ... Glad you mentioned polling speed because maybe u need to turn it up. I'll look into that
    I already tried with the polling speed maxed out (for the essential channels), but I still had a long list of PID's I was recording. I need to keep the number of PID's to a bare minimum some time and try. I don't know what all affects the resolution, but I figured I would try it.

  3. #23
    Advanced Tuner AKDMB's Avatar
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    Quote Originally Posted by murfie View Post
    Base will be used when one of the tables under spark correction section has a larger effect on borderline value than knock advance/retard. I think it is used as a "catch all" to include cylinder to cylinder offset. The other areas will show their own correct source.
    I'm still seeing Base as my spark source even though my Lambda/IAT/ECT modifiers are zeroed out for normal operating conditions. I have my MBT tables set 4 degrees higher than borderline and with my last revision I tried maxxing out the cylinder pressure limit table too. Spark pretty much does as commanded at WOT though. The only caveat is that the Knock Sensor does not add any timing, it sits at zero. I have seen it still pull timing, but it never adds once it transtitions to base.

  4. #24
    Advanced Tuner AKDMB's Avatar
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    I tried setting my spark correction settings (Lambda, IAT and ECT Modifiers) back to stock, and I am still seeing my knock sensors read exactly Zero when the spark source goes to base at WOT.

    Here is my current tune (stock tune for comparison) and a datalog (seems like the file was too big to upload, so this log just shows the WOT portion)


    Tune 19,With Spark Correction, 0.850 Lambda, Same Timing as before, 26 CPL, No Tip In Mgmt, KS c.hpt

    Stock 2012 Mustang V6 Performance Pack Tune.hpt

    test log.hpl

  5. #25
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    Quote Originally Posted by AKDMB View Post
    I tried setting my spark correction settings (Lambda, IAT and ECT Modifiers) back to stock, and I am still seeing my knock sensors read exactly Zero when the spark source goes to base at WOT.

    Here is my current tune (stock tune for comparison) and a datalog (seems like the file was too big to upload, so this log just shows the WOT portion)


    Tune 19,With Spark Correction, 0.850 Lambda, Same Timing as before, 26 CPL, No Tip In Mgmt, KS c.hpt

    Stock 2012 Mustang V6 Performance Pack Tune.hpt

    test log.hpl
    I don't know if this will help, but your Lambda Spark Base MBT table is correcting by -2.56 degree's at 0.85 lambda, so your MBT becomes that corrected number, which then puts it same of lower than the calculated Borderline number.

    Try making the correction zero at 0.85 to 1.0 lambda.

  6. #26
    Advanced Tuner AKDMB's Avatar
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    Quote Originally Posted by Plimmer View Post
    I don't know if this will help, but your Lambda Spark Base MBT table is correcting by -2.56 degree's at 0.85 lambda, so your MBT becomes that corrected number, which then puts it same of lower than the calculated Borderline number.

    Try making the correction zero at 0.85 to 1.0 lambda.
    I had the spark correction effectively turned off in my last tune and still saw this issue.

    Here's that log (this one was too long as well, it does show the spark source transition to base at 3800 RPM) and tune.

    Tune 17,0.850 Lambda, Same Timing as before BUT NO C.P.L., No Tip In Mgmt, KS can add ONLY 2 Deg.hpt

    shortened log .85 Lambda No CPL.hpl

  7. #27
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    Zero out the cells from 4000 to 6500 of your cylinder to cylinder offset. You can zero out the multiplier tables as well or not. With out a PID for each individual cylinder I don't think it displays accurate information when one cylinder can be 2* difference in spark advance than another. It was subtracting 2 degrees

    Zero out the piston rattle table. it was adding a degree

    Change the 200 to 220 in the engine coolant temp spark correction. it was adding .75 *

    Thats a -.25*, when your knock goes to 0 your source goes to base as this is modifying the borderline value of 15 more than the knock advance. Your spark PID displays 14.8=15*-.25

  8. #28
    Advanced Tuner AKDMB's Avatar
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    Quote Originally Posted by murfie View Post
    Zero out the cells from 4000 to 6500 of your cylinder to cylinder offset. You can zero out the multiplier tables as well or not. With out a PID for each individual cylinder I don't think it displays accurate information when one cylinder can be 2* difference in spark advance than another. It was subtracting 2 degrees

    Zero out the piston rattle table. it was adding a degree

    Change the 200 to 220 in the engine coolant temp spark correction. it was adding .75 *

    Thats a -.25*, when your knock goes to 0 your source goes to base as this is modifying the borderline value of 15 more than the knock advance. Your spark PID displays 14.8=15*-.25
    I will try out this change today, hopefully, thanks for the advice.

    ^^edit, make that monday lol
    Last edited by AKDMB; 10-13-2017 at 10:32 PM.

  9. #29
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    Sorry to bump an old thread, but there was never an answer. "Base" refers to MBT tables. If you're running at base, you're running MBT. MBT is the base timing that your ecu attempts to reach. It's the final goal. So if you see base as the source, just means you're running at max tq at that moment. This is easy to see if you log MBT. The reason the source is called base instead of MBT is because base timing is derived from MBT tables and a few other modifying tables, so base is rarely what's actually written in MBT tables.

  10. #30
    Advanced Tuner metroplex's Avatar
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    In the case of my 2014 SHO I eventually got it to run off BKT which is normally what should happen. You can tweak BKT because it is almost always lower than MBt, but base or MBT is the theoretical spark for max torque or whatever scientific explanation it means, and really shouldn?t be adjusted to get the spark you want.

  11. #31
    Advanced Tuner veeefour's Avatar
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    Quote Originally Posted by metroplex View Post
    In the case of my 2014 SHO I eventually got it to run off BKT which is normally what should happen. You can tweak BKT because it is almost always lower than MBt, but base or MBT is the theoretical spark for max torque or whatever scientific explanation it means, and really shouldn?t be adjusted to get the spark you want.
    Not quite, you explained how the GM or MOPAR works where MBT is just a representation model.

    However MBT has to be adjusted in FORD because only Ford adds knock to the equation: BRD+KNOCK=MBT

  12. #32
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    Quote Originally Posted by veeefour View Post
    Not quite, you explained how the GM or MOPAR works where MBT is just a representation model.

    However MBT has to be adjusted in FORD because only Ford adds knock to the equation: BRD+KNOCK=MBT
    You are right.
    Borderline = MBT. This is how GM or Mopar work. Hope it doesn't detonate too heavy and pull timing only after it happens.

    Ford defines and actually uses MBT, allowing for conservative borderline tables and knock advance so the ECU is what finds the actual borderline of detonation(before running into heavy detonation) or it runs advance up to MBT no higher.

    MBT changes with Lambda, which is defined in the ECU. You can adjust for the type of fuel if its combustion has a significant flame speed difference from gasoline. That's why E85 likes a few degrees more advance than race fuels.
    Generally(not always) a higher specific gravity a fuel has the slower it burns, the more spark advance you need for MBT.
    Less octane Pump gasoline is usually lower specific gravity. Leaded fuels are very low specific gravity. Octane boosters are usually higher density molecules/elements like lead with various specific gravities. If they settle out of the gasoline they are higher specific gravity, if they don't they are lower.
    Last edited by murfie; 4 Days Ago at 05:48 AM.
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  13. #33
    Advanced Tuner metroplex's Avatar
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    So when did Ford use this new strategy? MBT had always been kind of a comparison table. There are adders/etc for BKT and MBT but the PCM would use whichever was lower. So if you added a bunch of spark to BKT and it exceeded the MBT table, then the PCM would use the lower (e.g. MBT). Back to my post about the SHO years ago, it would always use Base for whatever reason at WOT. Eventually I got it to work off BKT and was able to add spark using the BKT table like I've been doing for 15+ years. So whatever spark I added would show up as a higher final spark. That's how I did it with EEC-V, Copperhead, etc... Maybe you're saying the same thing in a theoretical explanation but that's what I've been basically doing since the days of the 2V modular V8s (Also accounting for adders/modifiers). Back in the day of the 2V modular V8s, a lot of the tuners would copy MBT over to BKT for the highest octane fuel.

  14. #34
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    The Logic is and always has been the table with the lowest value(table = spark source, there's more than just base and borderline). MBT= minimum spark advance for best torque. Anything that has a knock sensor has knock advance. Knock advance only gets added to the borderline values. Think of the knock sensor as another borderline correction table. It makes up for what all the other borderline correction tables don't.

    Borderline and MBT are not the same thing like GM or Dodge treat them. Because when you are detonation limited, you are not making the best torque. Add some octane and reach the MBT value and you will make the best torque. Add some more octane and increase advance past MBT, and you will not be making the best torque. GM or dodge can easily do this with inexperienced tuners, and people who don't understand what MBT actually is. Because they don't define and use MBT, rather their strategy is "more octane = more spark advance".

    Ford designs their engines to run near MBT not detonation limited under heavy load. This is a reliability thing. Normal 93 ron+mon/2 gas can and will get you to MBT on a stock car. Start increasing air flow and MBT doesn't change(defined up until the tables load axis, usually 1.1 which covers anything NA), the borderline of detonation changes. Its usually peak torque where detonation is most likely to happen. Understanding the relationship is how you safety determine if you should add spark or add more Boost. You don't always just keep adding spark to increase torque.
    Last edited by murfie; 3 Days Ago at 11:44 AM.
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  15. #35
    Advanced Tuner metroplex's Avatar
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    So on EcoBoost you could see something like 21 degrees advance at the highest air load / RPM region on the MBT table, but BKT/final spark is somewhere around 1 degree advance like at air load 2.20
    On my 3.5 transverse EcoBoost if I had just left that as is, there was a lot of power left on the table. So I steadily increased BKT until I got to a happy medium with respect to knock and power using E30+. Bottom line was that I had to raise BKT slightly more than stock which was always lower than MBT. There was no way I can run at full MBT spark even with stock boost levels, and the factory strategy didn't seem to run at MBT either.

    On the N/A Ford applications, like my S197 GT 4.6 3V or heck my Explorer N/A 3.5, it was never a problem running at or near MBT spark levels with just 93 octane fuel.

  16. #36
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    Quote Originally Posted by metroplex View Post
    So on EcoBoost you could see something like 21 degrees advance at the highest air load / RPM region on the MBT table, but BKT/final spark is somewhere around 1 degree advance like at air load 2.20
    On my 3.5 transverse EcoBoost if I had just left that as is, there was a lot of power left on the table. So I steadily increased BKT until I got to a happy medium with respect to knock and power using E30+. Bottom line was that I had to raise BKT slightly more than stock which was always lower than MBT. There was no way I can run at full MBT spark even with stock boost levels, and the factory strategy didn't seem to run at MBT either.

    On the N/A Ford applications, like my S197 GT 4.6 3V or heck my Explorer N/A 3.5, it was never a problem running at or near MBT spark levels with just 93 octane fuel.
    It's always good to look at the stock calibration as a whole, and make sure it doesn't look like ford was doing a rush job. 18+ mustang gt and 20+ gt500 I think they were.
    "We can never be right, we can only be sure that we are wrong"- feynman