follow ft86club on our blog, twitter or facebook.
FT86CLUB
Ft86Club
Delicious Tuning
Register Garage Community Calendar Today's Posts Search

Go Back   Toyota GR86, 86, FR-S and Subaru BRZ Forum & Owners Community - FT86CLUB > Technical Topics > Software Tuning

Software Tuning Discuss all software tuning topics.

Register and become an FT86Club.com member. You will see fewer ads

User Tag List

Reply
 
Thread Tools Search this Thread
Old 07-09-2025, 02:55 AM   #1
callisto
Member
 
Join Date: Nov 2021
Drives: 2019 Subaru BRZ
Location: NA
Posts: 97
Thanks: 67
Thanked 69 Times in 37 Posts
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Post 18-19 MT EU have a more detailed DI/PI ratio tune than 17-20 JP/US

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)
Attached Images
    

Last edited by callisto; 11-10-2025 at 06:36 AM. Reason: add GDI firing angle change
callisto is offline   Reply With Quote
The Following 3 Users Say Thank You to callisto For This Useful Post:
RedReplicant (07-10-2025), Tatsu333 (07-19-2025), tomm.brz (07-24-2025)
Old 07-16-2025, 04:46 PM   #2
gpvecchi
Senior Member
 
gpvecchi's Avatar
 
Join Date: Mar 2018
Drives: Toyota 86 GT Limited PP (Model G)
Location: Italy
Posts: 1,048
Thanks: 411
Thanked 355 Times in 199 Posts
Mentioned: 14 Post(s)
Tagged: 0 Thread(s)
Perhaps because the EU spec require 98 octanes fuel? JP require Premium fuel, so 96 octanes. The US are probably even lower.
gpvecchi is offline   Reply With Quote
Old 07-18-2025, 06:56 AM   #3
RToyo86
Senior Member
 
RToyo86's Avatar
 
Join Date: Mar 2018
Drives: 17 Asphalt 86
Location: Ottawa
Posts: 2,384
Thanks: 1,878
Thanked 2,629 Times in 1,285 Posts
Mentioned: 16 Post(s)
Tagged: 0 Thread(s)
Quote:
Originally Posted by gpvecchi View Post
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.
RToyo86 is offline   Reply With Quote
Old 07-19-2025, 11:59 AM   #4
Tatsu333
Senior Member
 
Join Date: Jan 2017
Drives: 2020 BRZ Sport Tech RS
Location: Canada
Posts: 425
Thanks: 519
Thanked 324 Times in 179 Posts
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quote:
Originally Posted by callisto View Post
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...
__________________
Tatsu333 is offline   Reply With Quote
Old 07-19-2025, 12:10 PM   #5
callisto
Member
 
Join Date: Nov 2021
Drives: 2019 Subaru BRZ
Location: NA
Posts: 97
Thanks: 67
Thanked 69 Times in 37 Posts
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quote:
Originally Posted by Tatsu333 View Post
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?)
callisto is offline   Reply With Quote
The Following User Says Thank You to callisto For This Useful Post:
tomm.brz (07-24-2025)
Old 07-23-2025, 01:20 AM   #6
tomm.brz
Senior Member
 
Join Date: Jan 2017
Drives: brz 2017 hksv2
Location: italy
Posts: 2,276
Thanks: 515
Thanked 1,121 Times in 811 Posts
Mentioned: 70 Post(s)
Tagged: 0 Thread(s)
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
tomm.brz is offline   Reply With Quote
The Following User Says Thank You to tomm.brz For This Useful Post:
Tatsu333 (07-24-2025)
Old 07-23-2025, 06:50 PM   #7
callisto
Member
 
Join Date: Nov 2021
Drives: 2019 Subaru BRZ
Location: NA
Posts: 97
Thanks: 67
Thanked 69 Times in 37 Posts
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quote:
Originally Posted by tomm.brz View Post
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.
callisto is offline   Reply With Quote
The Following User Says Thank You to callisto For This Useful Post:
tomm.brz (07-24-2025)
 
Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
GT86 2018 Driver side is lower than my passenger side/ lopsided Sioux Suspension | Chassis | Brakes -- Sponsored by 949 Racing 6 08-01-2022 12:18 AM
Why is a Stage 1 tune better than stock? Zinnober Software Tuning 9 08-22-2021 08:05 PM
What should I do if car has been unused for more than 5 months dazhbucked Mechanical Maintenance (Oil, Fluids, Break-In, Servicing) 15 03-29-2021 09:19 AM
BRZ 2018 AT to MT gear ratio Septor Engine, Exhaust, Transmission 22 01-21-2019 04:42 PM
Does anybody know if the tune from the vortech is better than the ecutek? Frsexxxy Forced Induction 16 04-08-2013 12:53 PM


All times are GMT -4. The time now is 07:12 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2025, vBulletin Solutions Inc.
User Alert System provided by Advanced User Tagging v3.3.0 (Lite) - vBulletin Mods & Addons Copyright © 2025 DragonByte Technologies Ltd.

Garage vBulletin Plugins by Drive Thru Online, Inc.