Injector resize "Smart Adjust"

Nistune topics related specifically to the 6303 cpu

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Sawgunner
 

Posts: 6
Joined: Sun Feb 16, 2020 10:36 pm

Injector resize "Smart Adjust"

Post by Sawgunner »

Trying to figure out a few issues, thought I would throw up a quick post.

The simple part is what is the benefit of the injector resize smart adjust feature? Seems to create some funky K/TIM numbers that would skew the whole show.

Hard part is I am trying to figure out why my ecu is wanting to hang onto closed loop/apply trims when well into boost. Inconsistent to a degree but I am able to replicate with a shift from 4th gear to 5th gear and applying full throttle. Happens 4 out of 5 times. I have tried to do my injector resize/maf resize and load scales to all comply with "keeping close to factory TP indexing". I have also tried factory rb25 fuel and ignition load scales. WOT max load hits 100-104TP. "0 boost area" is 46-50TP or so.

R33 GTS25T Skyline
FMIC
Exhaust
ID1050X injectors/Radium fuel rail/Walbro 450 Pump/Aeromotive FPR
HPX-N1 Maf in custom housing, 31% Scaling

Please note tune is far from complete, still working through tuning and upgrades before dyno session.

Please see attached Log and Tune file.
Reference Log at 36 to 40 seconds, note climbing afr well outside of closed loop and trimming there.

Still also have throttle transition richness/stutter/misfire that i cant seem to get rid of. Have tried lots of things and I am REALLY not wanting to give up on Nistune but it is getting exhausting. Hopefully I can get some more insight.

Thanks for all the hard work and support.
John
Attachments
HPX-N2_31_percent_2.985_inch ID1050x injectors 2.bin
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leantest_2020-07-14_1609_39.csv
(104.69 KiB) Downloaded 63 times
Matt
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Re: Injector resize "Smart Adjust"

Post by Matt »

The point of the smart adjust is to first resize your K constant close to factory and then adjust the remainder with your TIM

For example if we resize S13 SR20DET with Z32 MAF and 740CC injectors only, then we 2x the K for MAF, and then 1/2x the K for injectors. So we end up with near factory K value

If we instead resize with 1000CC injectors, then the same as above applies but then adjust the remainder with TIM

Things might get funky if you are using custom MAF curve or resizing to something that is not in the MAF drop list (where we have a predefined HP number). In that case, don't use the smart adjust for injector resize. There are other options in the drop down

If you disconnect the O2 sensor, do you see the same issue happening?
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HCR32 closed loop.png
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Matt
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Re: Injector resize "Smart Adjust"

Post by Matt »

Just looking int this further. There are no trim adjustments until 0:37.219 in the log file.

Then it pulls out 12% STFT to get 14.02:1 AFR at this point

Load is 72 here, but factory load is 56 in the orginal scales

12 16 20 24 28 32 36 40 44 48 52 56 60 64 72 80

Would suggest using original scales, and adjusting K constant to suit.

So changes 12 - 112 back to 12 - 80 TP scales

Then for that resize, reduce K by 30% , and add 30% to TIM. That will get you running in factory scale range and may stop it trimming on you here
Attachments
2020-07-25 17_40_30-Nistune [HCR32 SKYLINE (RB20DET) (Version_ 4)].png
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2020-07-25 17_39_21-Nistune [HCR32 SKYLINE (RB20DET) (Version_ 4)].png
(108 KiB) Downloaded 667 times
Sawgunner
 

Posts: 6
Joined: Sun Feb 16, 2020 10:36 pm

Re: Injector resize "Smart Adjust"

Post by Sawgunner »

Matt,

Thanks for the initial response and also for looking into it further.

I had considered this but maybe was a little standoffish because that will shift my load points left quite a bit. I was hoping to not have to change a lot of the map but I will certainly give it a try if that's what it takes, not the end of the world. Would you suggest running the ignition scale in the factory 12-96 range as well? That would essentially run it in the fuel load scale to 80 with an overboost column in ignition at 96.

I am still concerned with my fast throttle enrich. The tracer does not move while observing those scales, it just sits on the 1.9V end all the time and I get very strong misses at mid rpm and need to make quick throttle movements. I had read over a forum post somewhere suggesting that the rb20 ecu with the rb25 may have an issue deep in the code for throttle enrich that cant be fixed?

Thank you very much for the further research, car runs amazing besides those couple issues, but big issues they are.
John
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