SUPRA ULTIMATE JB4 GUIDE AND LOG REVIEW (V1)

[Phantomx]

yea its kinda doing the same thing with the trims on e30 as well they spike up then settle, I can of course turn the boost back a bit, everytime I put 24 in the trims are not happy but 23.5 seems to make it a little better

E30 24psi run trims maxed a bit then settle
https://datazap.me/u/phantomx2k/bef-jb4map6?log=0&data=1-3-4-12-14-18-19&hg=19-1-4-3-18-14-12

Here is E30 with 23.5 psi instead trims seem happier
https://datazap.me/u/phantomx2k/bef-jb4map6-tweaked?log=0&data=1-4-14

I can see if Terry can up the fueling Or I’ll probably need to dial it back just tick…

Sponsored

 

[ColonelAdama]

yea its kinda doing the same thing with the trims on e30 as well they spike up then settle, I can of course turn the boost back a bit, everytime I put 24 in the trims are not happy but 23.5 seems to make it a little better

E30 24psi run trims maxed a bit then settle
https://datazap.me/u/phantomx2k/bef-jb4map6?log=0&data=1-3-4-12-14-18-19&hg=19-1-4-3-18-14-12

Here is E30 with 23.5 psi instead trims seem happier
https://datazap.me/u/phantomx2k/bef-jb4map6-tweaked?log=0&data=1-4-14

I can see if Terry can up the fueling Or I’ll probably need to dial it back just tick…

Until he gets you more fueling just back off on boost till trims stay <45ish

 

[razorlab]

I’m happy to make any changes you all would want in the BEF file, just send me the one you are using and what you need.

 

[ColonelAdama]

Here is E30 with 23.5 psi instead trims seem happier
https://datazap.me/u/phantomx2k/bef-jb4map6-tweaked?log=0&data=1-4-14

sorry I didn't see the second log yet,

this second one looks great, you can run it

 

[ColonelAdama]

Here's a great example of a Map 4 that is dialed in nicely:

https://datazap.me/u/coloneladama/log-1708732537?log=0&data=1-3-4-9-11-14-18-25-26-27-28

@Foxrider0314 's car getting the most out of Map 4 after a few duty bias/FF revisions.

• see all 6 cyl ign timing converged and climbing to 15 deg at redline, no drops or separation
• boost within 1 psi of target at all times
• No overboost or big throttle cuts
• not maxing trims or sustaining high afr

 

[Foxrider0314]

Here's a great example of a Map 4 that is dialed in nicely:

https://datazap.me/u/coloneladama/log-1708732537?log=0&data=1-3-4-9-11-14-18-25-26-27-28

@Foxrider0314 's car getting the most out of Map 4 after a few duty bias/FF revisions.

• see all 6 cyl ign timing converged and climbing to 15 deg at redline, no drops or separation
• boost within 1 psi of target at all times
• No overboost or big throttle cuts
• not maxing trims or sustaining high afr

Here's a great example of a Map 4 that is dialed in nicely:

https://datazap.me/u/coloneladama/log-1708732537?log=0&data=1-3-4-9-11-14-18-25-26-27-28

@Foxrider0314 's car getting the most out of Map 4 after a few duty bias/FF revisions.

• see all 6 cyl ign timing converged and climbing to 15 deg at redline, no drops or separation
• boost within 1 psi of target at all times
• No overboost or big throttle cuts
• not maxing trims or sustaining high afr

Thanks again for helping me understand how the jb4 actually works and not just telling me to plug in certain numbers.. I've always had high hp Subarus but this jb4 thing it's completely new to me.. again I really appreciate you teaching the community.. This is what this forum is supposed to be for..

 

[Phantomx]

I see the timing your talking about. Trims were all the way up to almost maxed out (same as what i see in mine) where it goes up To 46 and kinda hangs up there for 1000rpm and adjusts down again into the 30’s. So I see that in my logs too so that makes me feel better LOL. Now that I see that though I think your right avg_ign isn’t helping me or I just don’t understand exactly what that value truly is.

Running lower boost I see the timing is a bit hotter vs mine on higher boost timing comes in around 11 or 12 with any kind Of tuning so far even with MHD OTS or MAP 0 I was still around 11/12 degrees. Now when I turn the boost down to almost stock then sure I see timing jump to 19* but as the boost goes up timing comes down, at least on my 2020 I don’t know what I can do to get say from 12 to 15 open to thoughts or suggestions

@razorlab I wouldn’t even know what to ask to change to be honest…

It would be awesome to see a graph of a similar car/mods with either custom tune or this combo and 23/24psi and what timing looks like, if it can run a bit hotter i’m sure it would make more power but that is the tuning challenge right, how much fuel/air/timing can I squeeze in most efficiently without going bang and making the most power.

I’m going to dial my down to 23.5 psi it just seems to be happier for whatever reason 24 it’s like ”no don’t do that“.

I‘m not sure what other duty bias setting to tweak (using your values Colonel) FF is 60, IAT spoofed (Terry at Burgers settings).

Terry also mentioned that the boost drops were because the DME_BT dropped he said that was harder to correct but i’m not sure what that exactly means…

 

[Phantomx]

If anyone is interested I found this about avg_ign (this is for the N54 and some of the other N and S engines but maybe a bit different possibly for the B58 but it seems helpful and most of the settings seem to relate to the JB4 in general regardless of engine though values may be different for different engines classes the definitions seem to be about the same)

The JB4 uses this activity and the overall value of the ignition curve to calculate the Avg Ign (Average Ignition Retard) value. Newer JB4 firmware versions allow you to log timing from cylinders 2-6 in addition to cylinder 1 to provide a more comprehensive view of timing advance and knock. This must be enabled by entering the appropriate 6cyl timing value under the user adjustment page.
　
Avg Ign: Average Ignition Retard. A JB4 calculated value with a range of 0 - 6 that represents the average amount of timing below the maximum possible curve over a short term window. Lower values indicate a higher overall ignition advance while higher values indicate a lower overall ignition curve. This calculation is used by the JB4 for evaluating octane content by both map 5 (auto learning) and map 3 (methanol injection). Values below about 1.5 result in full Map 3 or Map 5 scheduled boost levels.
Values between about 1.5 and 6.0 result in lower and lower boost targets as an added safety feature for these two maps. As a general rule when using meth, race gas, or heavy E85 mixtures look for values below 2.0. When using pump gas expect values of 5 or higher.

So it appears to work with the 6cyl timing setting to do a calculation that after reading that a few times i’m still not grasping entirely.

https://f30.bimmerpost.com/forums/showthread.php?t=1379509 this has a very detailed explanation of like everything

This was also really good about looking at IGN_1 timing

Ign1: Ignition Advance is the number of crank degrees BTDC (Before Top Dead Center) when the spark is turned on to ignite the fuel/air mixture in the cylinder. Generally higher engine loads/boost levels require less advance because the burning process progresses faster (less time to complete) under higher cylinder pressures. Higher engine rpm generally requires more ignition advance because there is less time for the cylinder pressure to build up before the piston starts it’s downward stroke.
The displayed ignition advance value if for cylinder #1 but the DME can adjust timing on a cylinder by cylinder basis using an advanced knock sensor system with long term (octane detection) and short term (knock detection) trims analogous to a fuel trims. The displayed values can change a large amount under light to moderate loads….. more than 30 degrees on some engines. WOT (Wide Open Throttle) will result in a much narrower range of values….. usually dish shaped with values in the 10 to 13 degree range over the ends of the rpm band and a minimum valley value of about 6 - 8 degrees.

Of more importance is watching out for sharp drops of more than 3 degrees in the engine high torque/power band…. typically in the > 4500 rpm range. Sharp drops of 3 degrees from one scan to the next indicate potential knock activity and are a general indication that the boost curve may be set too high for the available octane. Drops randomly throughout runs especially on pump grade fuels are expected but repeated drops in the same gear indicate an overly aggressive tune.

Also note the DME will raise and lower advance as a function of normal mapping like during traction control events, gear changes, etc, and such drops are completely normal.


Seems values between 10-13 are optimal if i read that correctly? At least on the N54 and how that translates to the B58 hell I don’t know

 

[ColonelAdama]

Now when I turn the boost down to almost stock then sure I see timing jump to 19* but as the boost goes up timing comes down, at least on my 2020 I don’t know what I can do to get say from 12 to 15 open to thoughts or suggestions

I don't know if BEF vs stock map timing is a fair comparison. Wouldn't surprise me if the BEF dialed it down a little to run higher boost. For you, 15 at redline may be unrealistic, and that's fine because you're making way more power lol. follows what you said about the ign1 timing above.

Terry also mentioned that the boost drops were because the DME_BT dropped he said that was harder to correct but i’m not sure what that exactly means…

he just means that there is something the car is seeing that it doesn't like, that causes it to pull back the DME boost target. ie. overboost, knock, fuel ceiling, etc. could be any number of things, thats why he says it can be hard to correct. I think that last 23.5 map that you shared was a good spot for your car, so you should enjoy it there!

 

[Phantomx]

I don't know if BEF vs stock map timing is a fair comparison. Wouldn't surprise me if the BEF dialed it down a little to run higher boost. For you, 15 at redline may be unrealistic, and that's fine because you're making way more power lol

Oh man this makes my head hurt I have so much more research to do LOL

 

[ColonelAdama]

Oh man this makes my head hurt I have so much more research to do LOL

like you said above

Ign1: Ignition Advance is the number of crank degrees BTDC (Before Top Dead Center) when the spark is turned on to ignite the fuel/air mixture in the cylinder. Generally higher engine loads/boost levels require less advance because the burning process progresses faster (less time to complete) under higher cylinder pressures.

its probably intentional in the BEF, you could always ask Terry

 

[Gryph8n]

I reviewed my logs within the guidelines of this awesome thread. Lots of great info which is much appreciated. Looks like my map 4 has the most promise with matched FF to PWM curves, no dropped timing, DME BT peaking flat and no drop-off, etc.

I want to do a custom map 6 to fine tune and smooth out the power delivery.

Under map 6 boost for rpm, I presume I can set the absolute boost numbers to 20 or under? If fuel bias and duty bias is set at zero, then it goes to default?

Default for duty bias is 50? But what is default for fuel bias?

Do these settings look like a safe place to start with a 200 cell down and high-flow intake?

boost safety: 22.0
default wastegate position: 0
PID gain: 20
Auto shift boost redux: 60
FF/wastegate adaption: 50
TMAP setting: 2
Fuel open loop, boost drop, future use A, 6-cycl timing: 0

thanks for your input.

 

[i3igpete]

absolute can be below 20, but if below the dme_bt it will get clipped. there is an option to override dme_bt i am unsure how the car will behave. be aware that if the first row is below something like 6psi, the entire table will be treated as additive (this is how i run it, less sensitive weather and gear-to-gear boost threshold differences).

fuel bias does nothing on this engine platform unless you request special firmware from burger - note that this does NOT affect AFR targets

If you set Duty bias is too low, it will get clipped. Don't recall off the top of my head, but Adam said it's something like 25. This clip can also be removed with the custom firmware from Burger

 

[Phantomx]

I see an option to allow allow targets below the DMEBT but not necessarily disable it?

 

[Z4JR]

Hello @ColonelAdama

Would you mind looking at my map 1 logs?

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

Sponsored