SUPRA ULTIMATE B58 JB4 GUIDE AND LOG REVIEW (V1)

[ColonelAdama]

I see. You are the biggest JB4 proponent here so I was kind of surprised why you would move to flash tune but given you have some hardware upgrades in mind, this makes sense.

You still going to update us with news on the latest JB4 firmware or new tuning tricks for the MT crowd, right?

Yes of course I will continue to work with Jb4 for a while. I am a big proponent of it, I think its a great tool for *mostly* stock cars.

Actually heres a couple good tips for MT guys that I recently learned:

• Bit 6 (backend flash) actually gives the Jb4 more wastegate control, so if you are struggling with overboost no matter what you do with FF/duty, you can enable Bit 6 for more wastegate range.
• Bit (4?) 320i mode also seems to benefit MT cars as it gives the JB4 better wastegate control at lower boost.

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[GRMan]

Yes of course I will continue to work with Jb4 for a while. I am a big proponent of it, I think its a great tool for *mostly* stock cars.

Actually heres a couple good tips for MT guys that I recently learned:

• Bit 6 (backend flash) actually gives the Jb4 more wastegate control, so if you are struggling with overboost no matter what you do with FF/duty, you can enable Bit 6 for more wastegate range.
• Bit (4?) 320i mode also seems to benefit MT cars as it gives the JB4 better wastegate control at lower boost.

Nice, you contributed so much to this forum on JB4 and it would be great if you can still continue to.
So should bit 6 and bit 4 be enabled for all MT owners?

Also, do different firmwares have different usage of these bits or it applies to all firmware on the gen 2 b58?

 

[ColonelAdama]

Nice, you contributed so much to this forum on JB4 and it would be great if you can still continue to.
So should bit 6 and bit 4 be enabled for all MT owners?

Also, do different firmwares have different usage of these bits or it applies to all firmware on the gen 2 b58?

give it a try and see, I only got a handful of days to test it before dme went out, but it was smooth.

 

[ColonelAdama]

Well I finally flashed MHD today. Got 93 in the tank, so just Stage 2 93.

Only had time for a 20 minute drive, but here's my thoughts (compared to jb4):

• This 93 OTS map is almost as quick as my custom tune JB4 E30. Low end is way punchier, top end is a little less. No surprise with the much lower octane. Obviously E40 OTS will be much quicker than JB4 ever was.
• Throttle response, especially at lower rpms, is super snappy. I like it, feels like you can accelerate quicker lower in the rev range, even in "normal" driving.
• Absolutely no issue blowing my PS4S off through 1st and 2nd lol.
• Took a couple quick logs to make sure all looked good:
  • Looks pretty clean, couple cylinders timing corrections <3 degrees. Could put in a couple gal E85 but may as well go to E40 map at that point.
  • Much happier to see AFR at 12 for pump gas, and lower timing targets than stock. Much more appropriate for 93.
  • Seem to be hitting a tq limiter or something at lower rpm that keeps it from hitting boost target under 4000rpm, but don't feel it. perfectly smooth. Any ideas @razorlab ? https://datazap.me/u/coloneladama/log-1764180713?log=0&data=3-4-6-17-43&solo=43
    

But yeah, glad I finally made the jump. NGL, was nervous about the whole unlock/flash process (obviously, why I ran JB4), but no regrets! Will play around on OTS maps for a bit, then give E50 JB4 BEF a try, then next year will try to do my own MHD custom map.

 

[razorlab]

Well I finally flashed MHD today. Got 93 in the tank, so just Stage 2 93.

Only had time for a 20 minute drive, but here's my thoughts (compared to jb4):

• This 93 OTS map is almost as quick as my custom tune JB4 E30. Low end is way punchier, top end is a little less. No surprise with the much lower octane. Obviously E40 OTS will be much quicker than JB4 ever was.
• Throttle response, especially at lower rpms, is super snappy. I like it, feels like you can accelerate quicker lower in the rev range, even in "normal" driving.
• Absolutely no issue blowing my PS4S off through 1st and 2nd lol.
• Took a couple quick logs to make sure all looked good:
  • Looks pretty clean, couple cylinders timing corrections <3 degrees. Could put in a couple gal E85 but may as well go to E40 map at that point.
  • Much happier to see AFR at 12 for pump gas, and lower timing targets than stock. Much more appropriate for 93.
  • Seem to be hitting a tq limiter or something at lower rpm that keeps it from hitting boost target under 4000rpm, but don't feel it. perfectly smooth. Any ideas @razorlab ? https://datazap.me/u/coloneladama/log-1764180713?log=0&data=3-4-6-17-43&solo=43
    

But yeah, glad I finally made the jump. NGL, was nervous about the whole unlock/flash process (obviously, why I ran JB4), but no regrets! Will play around on OTS maps for a bit, then give E50 JB4 BEF a try, then next year will try to do my own MHD custom map.

Lol, I told you about the clutch slip protection on manual cars and there you are with a Torque Limiter 8388608, clutch slip protection.

Once you get to custom tuning, happy to help you out!

 

[ColonelAdama]

Lol, I told you about the clutch slip protection on manual cars and there you are with a Torque Limiter 8388608, clutch slip protection.

Once you get to custom tuning, happy to help you out!

Awesome, thank you! Does it mean there is actual slip or just to prevent it? Looks like load is held flat.

 

[nick470]

Hey guys, new member here looking for some initial feedback on my Map 0 and Map 1 logs.

Bone stock 2026 MT, 91 octane, located in Colorado so air density is absolutely pushing the compressor into a less efficient part of its operating range. This is on a JB4 with the fuel pressure add-on and an ethanol sensor. I have access to consistent E70.

Log is 4 pulls, two on Map 0 (forgot to turn TC off) and two on Map 1 (with TC off).

I'm a little unclear on where my FF and any other parameters should be set, as this thread has spanned a few changes in JB4 firmware so I'm not sure what information is current or out of date. I'm seeing some pretty substantial throttle closures in all the runs, and timing is... strange. Saw a comment mentioning that the way the JB4 reports timing has changed, so I want to make sure I'm interpreting the data correctly.

This is my first time playing with a piggy back system, but I've got a fair bit of experience on standalone systems (Megasquirt, Haltech, Hondata).

https://datazap.me/u/nick470/log-1764101344?log=0&data=1-4

 

[nick470]

Huge throttle closure can traction control kicking in. Set FF to 30 (FF is saved PER MAP) and try again.

Map 0, traction off, FF set to 30: https://datazap.me/u/nick470/log-1764371906?log=0&data=1-4-11-20-23

Map 1, traction off, FF set to 30: https://datazap.me/u/nick470/map-1-mkv-supra-mt?log=0&data=1-4-11-20

I'm a little surprised that the mid-pull FF shows at 39-40 in both logs, I had to go back and double check in the app but the FF is indeed set to 30 for both maps. Throttle closures are reduced, but had a dip to 70s around 3500rpm in Map 0 and some more substantial dips in Map 1

 

[ColonelAdama]

Map 0, traction off, FF set to 30: https://datazap.me/u/nick470/log-1764371906?log=0&data=1-4-11-20-23

Map 1, traction off, FF set to 30: https://datazap.me/u/nick470/map-1-mkv-supra-mt?log=0&data=1-4-11-20

I'm a little surprised that the mid-pull FF shows at 39-40 in both logs, I had to go back and double check in the app but the FF is indeed set to 30 for both maps. Throttle closures are reduced, but had a dip to 70s around 3500rpm in Map 0 and some more substantial dips in Map 1

boost control is fine, just try to get your octane up

 

[nick470]

boost control is fine, just try to get your octane up

Can you clarify on how the JB4 reports ignition timing in the current firmware? I see Ign_1 is showing higher values than 2-5, which are decently correlated. On others' logs, I'm seeing all 6 are showing more similar values.

Additionally, am I seeing octane limitations even in Map 0? Or is this timing dip around 4500-5500 (in ign_1) something else, VANOS or otherwise?

If my local 91 is presenting limitations even in map 1 on a cool day (~50-60F air temps), I'm thinking I have 3 options:
1) stick with stock/map 0 for pump gas and just go straight to figuring out what the car is happy with on e30ish.
2) Put together a very mild map 6 for 91 and feed the car corn until its happy on map 1 or 2
3) play with spoofing a high IAT to get the car to pull timing and add fuel

 

[ColonelAdama]

1) stick with stock/map 0 for pump gas and just go straight to figuring out what the car is happy with on e30ish.
2) Put together a very mild map 6 for 91 and feed the car corn until its happy on map 1 or 2
3) play with spoofing a high IAT to get the car to pull timing and add fuel

All good options, you are on the right track.

 

[Dven11]

Hello @ColonelAdama! back for more lol We did a log for Map1 on my friend's 21 340i. Can you help us out? CA 91 pump gas.

Mods:
Intake
Charge Pipe
Catless Downpipe
Exhaust

https://datazap.me/u/dven11/log-1764890756?log=0&data=1-2-3-4-5-6-8-9-11-14-15-18-20-25-26-27-28-29

https://datazap.me/u/dven11/log-1764892324?log=0&data=1-2-3-4-5-6-8-9-11-14-15-18-20-25-26-27-28-29

 

[ColonelAdama]

Hello @ColonelAdama! back for more lol We did a log for Map1 on my friend's 21 340i. Can you help us out? CA 91 pump gas.

Mods:
Intake
Charge Pipe
Catless Downpipe
Exhaust

https://datazap.me/u/dven11/log-1764890756?log=0&data=1-2-3-4-5-6-8-9-11-14-15-18-20-25-26-27-28-29

https://datazap.me/u/dven11/log-1764892324?log=0&data=1-2-3-4-5-6-8-9-11-14-15-18-20-25-26-27-28-29

I'd drop FF by 10 and see if timing cleans up a bit

 

[Dven11]

I'd drop FF by 10 and see if timing cleans up a bit

Dropped the FF down by 10. Here is the new log:

https://datazap.me/u/dven11/log-1764911775?log=0&data=1-2-3-4-5-6-8-9-11-14-15-18-20-25-26-27-28-29

Let me know what you think, thank you!

 

[ColonelAdama]

Dropped the FF down by 10. Here is the new log:

https://datazap.me/u/dven11/log-1764911775?log=0&data=1-2-3-4-5-6-8-9-11-14-15-18-20-25-26-27-28-29

Let me know what you think, thank you!

I'd keep dropping it by 5-10 until boost is more like 18 psi. timing is still rough

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