razorlab's simple build(s)
Nov 8, 2017, 09:57 AM
#932
After driving it for a bit the last couple days I retract my statement. I would say it took care of about 75% of the issue.
Yes I used zeros for the areas that called for negative values.
It's for sure better overall but still does some grumbly bits at low throttle / low load cruise situations and now 1st and 2nd gear driving slow, the transition between some throttle and decel is super harsh. The car will buck pretty badly in 1st gear. Need to figure out why it's doing that all of a sudden. Is the 0 requested PW entry really supposed to be set to 0 PW adjustment?
Also now noticing that sometimes at highway cruise decel when IPW is at 0 (injectors are off) that the car sometimes maxes out positive STFT. Never seen that behavior before. Usually STFT's just go to zero.
Yes I used zeros for the areas that called for negative values.
It's for sure better overall but still does some grumbly bits at low throttle / low load cruise situations and now 1st and 2nd gear driving slow, the transition between some throttle and decel is super harsh. The car will buck pretty badly in 1st gear. Need to figure out why it's doing that all of a sudden. Is the 0 requested PW entry really supposed to be set to 0 PW adjustment?
Also now noticing that sometimes at highway cruise decel when IPW is at 0 (injectors are off) that the car sometimes maxes out positive STFT. Never seen that behavior before. Usually STFT's just go to zero.
And there are other complicating factors. One that I found for my Evo is that at ~1500-2000 rpm, some kind of off normal behavior occurs in the fuel system that causes the injectors to flow less and produce a range of lean AFR no matter how much I tweaked the PW linearization and air flow scaling tables. Its some kind of resonance phenomenon that can't be 100% tuned out. I could only resolve the issue by adding a fuel pressure pulsation damper to the fuel system. The problem exists for both the FIC2150s and ASNU1500s, and I believe it happens with any injector. I have spoken with a few after market companies about this, and its definitely a real issue that is common to modified fuel systems. Some OEMs even include a fuel pressure pulsation damper in their fuel systems.
Anyhow, best I can say at this point is that what you are seeing can be tuned out, and perhaps you may want to install a fuel pulse damper. I think I put together a strategy document for this kind of tuning. If you are interested, I can look around later this week to see if I can find it. As a warning though, it is a very time consuming process that requires a lot of effort. It requires many sets of observations and small changes to the tune to work through it.
Nov 8, 2017, 12:26 PM
#933
I've been there with the bucking and STFT's that you're experiencing. The transition from off-throttle in load load situations is sensitive to both the linearization values and the air flow scaling tables, and both will have an affect on AFR. Tuning both tables requires driving under certain conditions that allow the effects of either table to be observed. It took something like five tanks of fuel to work through this on the FIC2150s because they are slightly inconsistent, while I think I had the ANSU1500s dialed in with two tanks of fuel.
And there are other complicating factors. One that I found for my Evo is that at ~1500-2000 rpm, some kind of off normal behavior occurs in the fuel system that causes the injectors to flow less and produce a range of lean AFR no matter how much I tweaked the PW linearization and air flow scaling tables. Its some kind of resonance phenomenon that can't be 100% tuned out. I could only resolve the issue by adding a fuel pressure pulsation damper to the fuel system. The problem exists for both the FIC2150s and ASNU1500s, and I believe it happens with any injector. I have spoken with a few after market companies about this, and its definitely a real issue that is common to modified fuel systems. Some OEMs even include a fuel pressure pulsation damper in their fuel systems.
Anyhow, best I can say at this point is that what you are seeing can be tuned out, and perhaps you may want to install a fuel pulse damper. I think I put together a strategy document for this kind of tuning. If you are interested, I can look around later this week to see if I can find it. As a warning though, it is a very time consuming process that requires a lot of effort. It requires many sets of observations and small changes to the tune to work through it.
And there are other complicating factors. One that I found for my Evo is that at ~1500-2000 rpm, some kind of off normal behavior occurs in the fuel system that causes the injectors to flow less and produce a range of lean AFR no matter how much I tweaked the PW linearization and air flow scaling tables. Its some kind of resonance phenomenon that can't be 100% tuned out. I could only resolve the issue by adding a fuel pressure pulsation damper to the fuel system. The problem exists for both the FIC2150s and ASNU1500s, and I believe it happens with any injector. I have spoken with a few after market companies about this, and its definitely a real issue that is common to modified fuel systems. Some OEMs even include a fuel pressure pulsation damper in their fuel systems.
Anyhow, best I can say at this point is that what you are seeing can be tuned out, and perhaps you may want to install a fuel pulse damper. I think I put together a strategy document for this kind of tuning. If you are interested, I can look around later this week to see if I can find it. As a warning though, it is a very time consuming process that requires a lot of effort. It requires many sets of observations and small changes to the tune to work through it.
That would be awesome if you could share that document! I have my setup to log whenever the car is on so I can get tons of logs no problem.
Nov 8, 2017, 06:11 PM
#934
let me know you solve the bucking when transitioning from not much throttle to 0 throttle... mine does it as well, 1/2/3rd... 4th/5th not so much, but i think thats due to the gearing more than anything.
regarding you STFT still calculating while in fuelcut, thats not right; however I have the tables which control when STFT is calculated - so you can setup new minimum loads if you want.. i have it on mine, set to like 22 load or something because below that the AFR is dubious and STFT goes out of wack quickly and doesn't recovery quick enough...
regarding you STFT still calculating while in fuelcut, thats not right; however I have the tables which control when STFT is calculated - so you can setup new minimum loads if you want.. i have it on mine, set to like 22 load or something because below that the AFR is dubious and STFT goes out of wack quickly and doesn't recovery quick enough...
Nov 8, 2017, 06:29 PM
#935
regarding you STFT still calculating while in fuelcut, thats not right; however I have the tables which control when STFT is calculated - so you can setup new minimum loads if you want.. i have it on mine, set to like 22 load or something because below that the AFR is dubious and STFT goes out of wack quickly and doesn't recovery quick enough...
Nov 10, 2017, 12:15 AM
#936
of course, 59580004 right?
Code:
<scaling name="Load_div_2" units="Load" toexpr="x*2*10/32" frexpr="x*32/10/2" format="%.1f" min="0" max="300" inc="1" storagetype="uint8" endian="big"/> <table name="Disable STFT Calcs below this Load" address="57d6c" category="Misc" type="2D" scaling="Load_div_2"> <table name="RPM" address="6233e" type="Y Axis" elements="14" scaling="RPM"/> </table> <table name="Enable STFT Calcs above this Load" address="57d7e" category="Misc" type="2D" scaling="Load_div_2"> <table name="RPM" address="6233e" type="Y Axis" elements="14" scaling="RPM"/> </table>
Last edited by tephra; Nov 10, 2017 at 12:21 AM.
Nov 10, 2017, 07:20 AM
#937
of course, 59580004 right?
Code:
<scaling name="Load_div_2" units="Load" toexpr="x*2*10/32" frexpr="x*32/10/2" format="%.1f" min="0" max="300" inc="1" storagetype="uint8" endian="big"/> <table name="Disable STFT Calcs below this Load" address="57d6c" category="Misc" type="2D" scaling="Load_div_2"> <table name="RPM" address="6233e" type="Y Axis" elements="14" scaling="RPM"/> </table> <table name="Enable STFT Calcs above this Load" address="57d7e" category="Misc" type="2D" scaling="Load_div_2"> <table name="RPM" address="6233e" type="Y Axis" elements="14" scaling="RPM"/> </table>
Nov 10, 2017, 02:44 PM
#938
The normal tables (with values of about 80-140) control when the ECU transitions from Closed to Open loop, think of them as the maximum load that the car wil run in Closed loop. With these tables, you can only control the upper boundary...
These new tables control when the STFT is calculated based of the minimum load. I am not sure if thats the same thing as Open -> Closed loop, but I guess in affect it is*
They are 2 sets of tables because to give the system some hysterisis....
* I just checked my logs, and whilst STFT goes to 0 when load is under these tables, LTFT_InUse still stays at whatever the LTFT is (rather than droping to 0 - like the Open/Closed loop tables would demand if Load exceeds them).
These new tables control when the STFT is calculated based of the minimum load. I am not sure if thats the same thing as Open -> Closed loop, but I guess in affect it is*
They are 2 sets of tables because to give the system some hysterisis....
* I just checked my logs, and whilst STFT goes to 0 when load is under these tables, LTFT_InUse still stays at whatever the LTFT is (rather than droping to 0 - like the Open/Closed loop tables would demand if Load exceeds them).
Nov 10, 2017, 02:47 PM
#939
The normal tables (with values of about 80-140) control when the ECU transitions from Closed to Open loop, think of them as the maximum load that the car wil run in Closed loop. With these tables, you can only control the upper boundary...
These new tables control when the STFT is calculated based of the minimum load. I am not sure if thats the same thing as Open -> Closed loop, but I guess in affect it is*
They are 2 sets of tables because to give the system some hysterisis....
* I just checked my logs, and whilst STFT goes to 0 when load is under these tables, LTFT_InUse still stays at whatever the LTFT is (rather than droping to 0 - like the Open/Closed loop tables would demand if Load exceeds them).
These new tables control when the STFT is calculated based of the minimum load. I am not sure if thats the same thing as Open -> Closed loop, but I guess in affect it is*
They are 2 sets of tables because to give the system some hysterisis....
* I just checked my logs, and whilst STFT goes to 0 when load is under these tables, LTFT_InUse still stays at whatever the LTFT is (rather than droping to 0 - like the Open/Closed loop tables would demand if Load exceeds them).
Nov 10, 2017, 02:59 PM
#940
EvoM Guru
iTrader: (1)
So, whens the first track in this bucket?
Nov 10, 2017, 03:01 PM
#941
Probably not until after the holidays. The group I run with doesn't have an event at the track I go to until then, also... holidaze. Also, need to still tune the track tune... 
Trust me, I am itching to go back, but I want to make sure everything is on point before so I don't have a ride home in a flatbed again.
Trust me, I am itching to go back, but I want to make sure everything is on point before so I don't have a ride home in a flatbed again.
Nov 11, 2017, 06:30 PM
#944
Grabbed some in-action video of the Android head unit + Racecapture setup. GoPro kind of sucks in low light but oh well.
Oh also added a degree of timing and upped boost to 29psi peak to 28ish out the top. Made 430wtq this pull. I'm going to dial it back so I don't destroy the clutch.
Oh also added a degree of timing and upped boost to 29psi peak to 28ish out the top. Made 430wtq this pull. I'm going to dial it back so I don't destroy the clutch.
Last edited by razorlab; Nov 11, 2017 at 07:00 PM.
Nov 11, 2017, 07:25 PM
#945
whats the app on that headunit?
is yours a 2.0? what sort of vacuum does it make at idle, and under decel?
in your logs, when you tip-out, do you see the TPS close down to a really low value, then open up another couple of %? i think this is the cause of the decel jerk for me...
is yours a 2.0? what sort of vacuum does it make at idle, and under decel?
in your logs, when you tip-out, do you see the TPS close down to a really low value, then open up another couple of %? i think this is the cause of the decel jerk for me...