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-   -   18-19 MT EU have a more detailed DI/PI ratio tune than 17-20 JP/US (https://www.ft86club.com/forums/showthread.php?t=155458)

callisto 07-09-2025 02:55 AM

18-19 MT EU have a more detailed DI/PI ratio tune than 17-20 JP/US
 
4 Attachment(s)
2018 MT EU (ZA1JQ00G) and 2019 MT EU (ZA1JS20G), received a much more detailed DI/PI ratio tune (direct/port injection) than either US or JP markets received at any time during gen1. Perhaps this was in response to new emissions restrictions landing in the EU around that time? The tuning tables are perhaps incompatible with K00G since they're the newer expanded kind, but duly noted for those who wish to study and pass judgment on what might be the intended effect.

Relevant tables that changed, based on a detailed reading of as much of the code as I could find and all K00G/S10C-documented Injector Ratio tables:
  • Total Injection Ratio Port Warm - and copied to Cold/Hot in full, which no other series can cope with
  • PI Ratio ECT Compensation
  • PI Ratio ECT Compensation (Load)
  • PI Ratio Thresholds
  • PI Ratio Thresholds (Load)
  • PI Ratio Thresholds (RPM)
  • PI Ratio Thresholds (Unknown) - it's a default buried in the code somewhere
  • GDI Firing Angle (all five)

Screenshots attached; either left/middle/right, or top/middle/bottom, are S20G/the-difference/V00C (I haven't mapped out Q00G yet but it has the exact Warm table as MY2019 EU S20G). Note that I haven't researched at all how much of any of this can possibly be applied to a K00G-derived tune; I suspect I'll need to release a K00G expanded variant with larger tuning tables to support that. Someday-next!

Various notes: I've only considered EU, JP, US. In the screenshots, "V00C00G v1" is the pane showing the changes 18-19 EU makes relative to 17-20 JP/US. I'll release S10C.xml v4 soon with the PI Ratio table, but I have a lot of busywork left to do on S20G/U01A/V00G before I can release those. If there's other tables related to DI/PI that I should evaluate for differences, let me know.

EDIT: There is also a specific change to all of the GDI firing angle tables that is probably relevant to anyone reading this post, as DI/PI work in concert on this engine to manage cylinder cooling. S20G/V00C comparison image added, showing the new data present in all S20G tables. (2025-11-10)

gpvecchi 07-16-2025 04:46 PM

Perhaps because the EU spec require 98 octanes fuel? JP require Premium fuel, so 96 octanes. The US are probably even lower.

RToyo86 07-18-2025 06:56 AM

Quote:

Originally Posted by gpvecchi (Post 3615173)
Perhaps because the EU spec require 98 octanes fuel? JP require Premium fuel, so 96 octanes. The US are probably even lower.

Us spec recommends 93 AKI should should be 98 RON.
Minimum octane 91aki.

Tatsu333 07-19-2025 11:59 AM

Quote:

Originally Posted by callisto (Post 3615043)
2018 MT EU (ZA1JQ00G) and 2019 MT EU (ZA1JS20G), received a much more detailed DI/PI ratio tune (direct/port injection) than either US or JP markets received at any time during gen1. Perhaps this was in response to new emissions restrictions landing in the EU around that time? The tuning tables are perhaps incompatible with K00G since they're the newer expanded kind, but duly noted for those who wish to study and pass judgment on what might be the intended effect.

Relevant tables that changed, based on a detailed reading of as much of the code as I could find and all K00G/S10C-documented Injector Ratio tables:
  • Total Injection Ratio Port Warm - and copied to Cold/Hot in full, which no other series can cope with
  • PI Ratio ECT Compensation
  • PI Ratio ECT Compensation (Load)
  • PI Ratio Thresholds
  • PI Ratio Thresholds (Load)
  • PI Ratio Thresholds (RPM)
  • PI Ratio Thresholds (Unknown) - it's a default buried in the code somewhere

Screenshots attached; either left/middle/right, or top/middle/bottom, are S20G/the-difference/V00C (I haven't mapped out Q00G yet but it has the exact Warm table as MY2019 EU S20G). Note that I haven't researched at all how much of any of this can possibly be applied to a K00G-derived tune; I suspect I'll need to release a K00G expanded variant with larger tuning tables to support that. Someday-next!

Various notes: I've only considered EU, JP, US. In the screenshots, "V00C00G v1" is the pane showing the changes 18-19 EU makes relative to 17-20 JP/US. I'll release S10C.xml v4 soon with the PI Ratio table, but I have a lot of busywork left to do on S20G/U01A/V00G before I can release those. If there's other tables related to DI/PI that I should evaluate for differences, let me know.

It'd be interesting to see if there's any noticeable difference in day-to-day driveability between the two configurations. I might have a look at what I can apply through ECUTEK and give it a go...

callisto 07-19-2025 12:10 PM

Quote:

Originally Posted by Tatsu333 (Post 3615207)
It'd be interesting to see if there's any noticeable difference in day-to-day driveability between the two configurations. I might have a look at what I can apply through ECUTEK and give it a go...

Agreed! I'd love to know if it has any noticeable effect for anyone else. My last year of testing was U01A with injector and timing tables from S20G, but once I mapped enough ECUs to compare and find out that I'd reverted the U/V improvements to timing maps, I'm now doing a year of testing with just the mods I posted above to V. (Note that if you're on K00G or older that you may have to remap the table to fit, I think this is one of those that expanded to provide more tuning fidelity in the facelift era?)

tomm.brz 07-23-2025 01:20 AM

it's just emission related. nothing more
the new EU with so much PI instead of DI runs worse, specially with 95RON
less DI runs just better and less knocky


93AKI of US is much more quality than 98ron and even 100ron of europe.. i'd say at least 102 ron
that's why US rom have more ignition timing and more power


k00g doesn t have full closed loop fueling, from Q00G EU they implemented full closed loop same as US tunes, with expanded PI tables... still, they run shitty, US tunes are much better, and still K00G is more stable and runs better than >Q00G


When i can, i always convert to k00g, much much better


for shitty fuel quality , car has more power (because it knocks also less) with more DI than PI.. i use 10% max at full load
for better fuel quality you can raise PI to 20-25% or even 30% for e85, it gains a little power with same ignition timing

callisto 07-23-2025 06:50 PM

Quote:

Originally Posted by tomm.brz (Post 3615251)
it's just emission related. nothing more

That is excellent news, thank you for confirming (not sarcastic!), I appreciate the details and will study Q00G next.


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