SUPRA ULTIMATE JB4 GUIDE AND LOG REVIEW (V1)

[swrdply400mrelay]

Thanks for the info!

What are the limitations of the JB4 vs unlocked ECU with BM3/MHD?

My MT Supra just has a Function Werk catless DP and JB4.

JB4 biggest limitation is inability to control fueling. So it can only push up to 33% more fuel than the stock map calls for. This makes it harder to make big power with ethanol. Also makes it harder to run high boost below 4k rpm or so. An unlock with BM3/MHD would likely be much torquier, but I don't think the peak power would be that far off.

JB4 can't control timing either, so it just runs stock timing maps. Again, its fine, but prevents it from being as powerful as say, an E30 OTS map from BM3 or MHD.

It is easiest to view JB4 as an advanced boost controller rather than a conventional tune.

Edit: @swrdply400mrelay - Jesse says JB4 works with hypercore, so I'll take his word for it. I have never tuned any non-stock turbo car though, but would be willing to learn.

any problems tuning a MT? On Jesse’s website it says he’s not doing any maps with MT

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[Jesse DaBears]

Edit: @swrdply400mrelay - Jesse says JB4 works with hypercore, so I'll take his word for it. I have never tuned any non-stock turbo car though, but would be willing to learn.

Its pretty easy the biggest thing with upgraded turbos is watching fueling with ethanol. Best to use race gas, or add meth. If not will just have to keep boost limited.

The DAW Flow Max works really well same with pure800. Both shine with meth.

 

[Jesse DaBears]

any problems tuning a MT? On Jesse’s website it says he’s not doing any maps with MT

I do them for people who are having big issues if you arent IMO the juice isnt worth the squeeze right now.

 

[ColonelAdama]

any problems tuning a MT? On Jesse’s website it says he’s not doing any maps with MT

Yeah, they're kind of a pain in the ass

The strategy is to set boost targets 2-3psi higher than you actually want, then wastegate tune (FF and duty bias) until the boost stays 2-3psi below target for the entire pull. I just call it "underboosting". Credit to @Jesse DaBears for sharing this info.

If boost exceeds target, it gets rough. If you don't get close enough to target, also rough.

I ended up needing custom V24 JB4 firmware to unlock the internal WGDC range limits because I couldn't control the overboost. Probably not needed unless catless and MT.

I did learn recently that my car runs much better when I lower the PID response of the JB4 boost control.... but again, it would be another huge write-up to get into all the troubleshooting and tuning of my catless MT

 

[Jesse DaBears]

Yeah, they're kind of a pain in the ass

The strategy is to set boost targets 2-3psi higher than you actually want, then wastegate tune (FF and duty bias) until the boost stays 2-3psi below target for the entire pull. I just call it "underboosting". Credit to @Jesse DaBears for sharing this info.

If boost exceeds target, it gets rough. If you don't get close enough to target, also rough.

I ended up needing custom V24 JB4 firmware to unlock the internal WGDC range limits because I couldn't control the overboost. Probably not needed unless catless and MT.

Ive actually worked on quite a few more. Shoot me your most recent log. You should honestly get a hypercore lol. Lets mess around with it on a MT. I would honestly get you one at cost so we can test. Just dont kill me if your MT tells us to F off.

 

[Jesse DaBears]

This was the last 93 MT car we did.

They are definitely doable just this is about as far as i can take them so far. Maybe 10-20 more HP and thats even with an Eblend.

If anyone has issues ive never turned them away but I just dont know who wants to sit and do 20-30 logs to get it this good lol.

 

[ColonelAdama]

This was the last 93 MT car we did.

They are definitely doable just this is about as far as i can take them so far. Maybe 10-20 more HP and thats even with an Eblend.

If anyone has issues ive never turned them away but I just dont know who wants to sit and do 20-30 logs to get it this good lol.

I am surprised you are able to make so much torque. I actually have no problem running as much boost as I want 5k+ without MT shenanigans.

My problem area is 3.5-5k as you can see in the log from this morning:
https://datazap.me/u/coloneladama/log-1706645272?log=0&data=1-2-3-4-8-15-20

Low boost since I am still working on figuring out why DME_BT wants to jump all over the place in that RPM range.

As for the hypercore, I may have to defer that until I am 100% happy with the current map, and I appreciate your offer!

 

[Jesse DaBears]

I am surprised you are able to make so much torque. I actually have no problem running as much boost as I want 5k+ without MT shenanigans.

My problem area is 3.5-4.5k as you can see in the log from this morning:
https://datazap.me/u/coloneladama/log-1706645272?log=0&data=1-2-3-4-8-15-20

Low boost since I am still working on figuring out why DME_BT wants to jump all over the place in that RPM range.

As for the hypercore, I may have to defer that until I am 100% happy with the current map, and I appreciate your offer!

email me the csv im at my desk.

 

[ColonelAdama]

email me the csv im at my desk.

Emailed - also just fyi - you can download the CSV from the datazap link at the bottom right of the page.

so all my settings are there if anyone is curious.

 

[i3igpete]

I ended up needing custom V24 JB4 firmware to unlock the internal WGDC range limits because I

I can't remember if I asked you this already, did ever ask Terry what the deal was with additive map 6 not working on MTs? Was that just an s58 issue or does it affect us too?

 

[Jesse DaBears]

Emailed - also just fyi - you can download the CSV from the datazap link at the bottom right of the page.

so all my settings are there if anyone is curious.

Oh snap never knew you can redownload the CSVs right from datazap. Thats awesome. Now if only someone would make a mobile app that would work.

 

[ColonelAdama]

I can't remember if I asked you this already, did ever ask Terry what the deal was with additive map 6 not working on MTs? Was that just an s58 issue or does it affect us too?

He told me additive WGDC control worked similarly to absolute, and I have had the underboost technique working with additive a few times... Just found absolute to be more consistent.

The S58 guys said their MTs had to use absolute only - using similar underboosting.

Oh snap never knew you can redownload the CSVs right from datazap. Thats awesome. Now if only someone would make a mobile app that would work.

ha no kidding, I stick to JB4 app for mobile reviewing still.

 

[Hardac_]

After driving for a while I finally found some back roads to do a few pulls after work.

Here are some runs on Map 2 and Map 4.
https://datazap.me/u/adm613/log-1706653433?log=0&data=1-2-3-4-5-8-9-15-20-23-34&solo=23

I'm still trying to interpret all of this to any useful degree, but I feel like I'm like trying to read a book but while learning the sounds of letters.

 

[ColonelAdama]

After driving for a while I finally found some back roads to do a few pulls after work.

Here are some runs on Map 2 and Map 4.
https://datazap.me/u/adm613/log-1706653433?log=0&data=1-2-3-4-5-8-9-15-20-23-34&solo=23

I'm still trying to interpret all of this to any useful degree, but I feel like I'm like trying to read a book but while learning the sounds of letters.

Map 2 is all over the place but Map 4 has potential. lets work off of that. Just looks like overboost from DP that needs to get worked out.

Set FF to 47, set bit 1 on to keep it adapting poorly.

Duty biases for downpipe: start with these:

duty_15	duty_20	duty_25	duty_30	duty_35	duty_40	duty_45	duty_50	duty_55	duty_60	duty_65	duty_70
40​	40​	40​	42​	44​	46​	48​	50​	50​	50​	50​	50​

 

[zrk]

Oh snap never knew you can redownload the CSVs right from datazap. Thats awesome. Now if only someone would make a mobile app that would work.

You know it's on the list. Right after rewiring your entire fucking car.

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