Seeking more info on JB4 Map 6 tuning

[AJRMKV]

Put the jb4 in whatever exhaust flap mode you want, then restart the car. Should work just fine after that. I had the same issue. Contact burger for the license reset as well.

I’m having the same issue with my JB4
Regardless of how I set the BC button with the car on, off or in diagnostic mode.

ive completely lost the ability to control the exhaust flap with the sport button.On the fly control is pretty mandatory for me.

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[D K]

I was able to get the exhaust flap to remain open at all times. Startup, normal, and sport mode all have the flap open now. It sounds nuts even with a stock DP.

It took me a few tries to get it working this way. I used the BC button on the stalk and not the canflap on the JB4.

 

[Evolution]

I’m having the same issue with my JB4
Regardless of how I set the BC button with the car on, off or in diagnostic mode.

ive completely lost the ability to control the exhaust flap with the sport button.On the fly control is pretty mandatory for me.

Does the flap work normal if you unplug the jb4 from the diagnostic port?

 

[ColonelAdama]

I was able to get the exhaust flap to remain open at all times. Startup, normal, and sport mode all have the flap open now. It sounds nuts even with a stock DP.

It took me a few tries to get it working this way. I used the BC button on the stalk and not the canflap on the JB4.

That's how I have mine on. Left blinker canflap(BC) setting - opens the flap like 5 seconds after cold start. Super loud. Sucks that the two blinker OEM operation mode doesn't work at all.

 

[i3igpete]

I’m having the same issue with my JB4
Regardless of how I set the BC button with the car on, off or in diagnostic mode.

ive completely lost the ability to control the exhaust flap with the sport button.On the fly control is pretty mandatory for me.

https://www.supramkv.com/threads/exhaust-flap-closes-jb4.6933/#post-205183

So when you go to "OEM mode" with both flashers, you need to shut down the engine for the settings to save properly. It's probably overkill, but I got out of the car and locked the door to ensure the setting would stick. After that, I was able to confirm that exhaust flap now works as factory again: opens with sport button, while the car is stopped OR in motion. I'm using the R22 firmware.

I did NOT need to touch the "disable BC button" after doing this, though I can see it being useful to prevent it getting stuck in the override state again.

There is another factor where some folks claim the JB4 can get confused if you use BimmerCode to always start in Sport mode. Since I prefer to start in normal mode anyway, this also didn't affect me, but you may need to revert this setting as well.

 

[totalone]

Holly fucking shit... I have bmw with JB4 and FML it does not like JB4, I am no tuner but even I can feel the struggle pushing these engines.

This was one of the best threads i have read in some time about b58 ad jb4. I am currently on map4 with AA downpipe, MPE and Dinan Intake.

My question would be, with custom map6 when tunning, would it not be stable since drop in temperatures outside? For example at summer outside temps are in mid 90s where I am at, but currently its in mid 50s. Colder air more air? How would map6 adopt to this or you would have to adjust custom values like throttle response and boost targets?

 

[ColonelAdama]

Holly fucking shit... I have bmw with JB4 and FML it does not like JB4, I am no tuner but even I can feel the struggle pushing these engines.

This was one of the best threads i have read in some time about b58 ad jb4. I am currently on map4 with AA downpipe, MPE and Dinan Intake.

My question would be, with custom map6 when tunning, would it not be stable since drop in temperatures outside? For example at summer outside temps are in mid 90s where I am at, but currently its in mid 50s. Colder air more air? How would map6 adopt to this or you would have to adjust custom values like throttle response and boost targets?

Don't get discouraged, downpipes don't mesh well with the JB4 right out of the box. you need to do custom tuning to get it right. Just upload your Map 4 log to datazap and post the link here. 2500rpm to redline in 3rd gear.

As for ambient temps changing, you would want to take some logs when the temp goes back up to make sure timing still looks good. It won't change throttle response or boost targets, just timing.

 

[totalone]

Don't get discouraged, downpipes don't mesh well with the JB4 right out of the box. you need to do custom tuning to get it right. Just upload your Map 4 log to datazap and post the link here. 2500rpm to redline in 3rd gear.

As for ambient temps changing, you would want to take some logs when the temp goes back up to make sure timing still looks good. It won't change throttle response or boost targets, just timing.

I just think ill pull a trigger on unlock. its like fighting an uphill battle. The only concern is that I dont like this while not able to update after unlocking ECU as well as I dont see much negative feed back from unlock. makes me think its not that good. Usually there is always some negative feed back on tunes.

 

[ColonelAdama]

I just think ill pull a trigger on unlock. its like fighting an uphill battle. The only concern is that I dont like this while not able to update after unlocking ECU as well as I dont see much negative feed back from unlock. makes me think its not that good. Usually there is always some negative feed back on tunes.

If that's the route you want to go - it definitely will make more power.

I haven't seen any of your logs, so I'm not sure what battle you're fighting with the JB4. It's usually an easy fix, but if money/warranty is no issue - Femto unlock is the better way to go anyway.

 

[totalone]

If that's the route you want to go - it definitely will make more power.

I haven't seen any of your logs, so I'm not sure what battle you're fighting with the JB4. It's usually an easy fix, but if money/warranty is no issue - Femto unlock is the better way to go anyway.

Was on free way today on the way home and it was fairly free. Was able to pull from mid third into 5th.
Here are the logs. Temps are fairly low too, in 43F

https://datazap.me/u/kkulakou/log-1700107049?log=0&data=1-4

 

[ColonelAdama]

Was on free way today on the way home and it was fairly free. Was able to pull from mid third into 5th.
Here are the logs. Temps are fairly low too, in 43F

https://datazap.me/u/kkulakou/log-1700107049?log=0&data=1-4

Looks alright. Bump up FF to 45, Enable bit 1, Set boost safety to 23.

Next log, start in 3rd gear at 2000 rpm, WOT to redline, upshift and let off after couple seconds.

Need to get ECU_PSI up so trims improve and timing cleans up.

 

[i3igpete]

Was trying to google some context on what good IAT temperature deltas were, and found this useful post that Mike @ x-ph wrote awhile ago for the N54. The goal of trying to get the throttle to stick open at 100% kind of bugs me at a "first-principles" controls engineering level. A control variable should be SOMEWHERE within its authority range, even if it's just chilling at 90% or 10%.

https://f30.bimmerpost.com/forums/showthread.php?t=1379509

Throttle. One of the most misunderstood aspects of evaluating logs is throttle movement. Note that throttle should not necessarily stick at 100% open at full throttle. It should be mostly fully open but closing proportional to boost exceeding boost target. Throttle is an active system used along with the boost control PID to regulate boost dynamically. Extended periods of throttle closure of 2 seconds or more and 40% or more closure normally indicates that boost control adjustment is needed. Short throttle movement of less than 30% and less than 1 second are expected and normal.

(yes, I understand that boost is controlled using multiple different levers beyond wastegate and throttle angle).

 

[ColonelAdama]

Was trying to google some context on what good IAT temperature deltas were, and found this useful post that Mike @ x-ph wrote awhile ago for the N54. The goal of trying to get the throttle to stick open at 100% kind of bugs me at a "first-principles" controls engineering level. A control variable should be SOMEWHERE within its authority range, even if it's just chilling at 90% or 10%.

https://f30.bimmerpost.com/forums/showthread.php?t=1379509



(yes, I understand that boost is controlled using multiple different levers beyond wastegate and throttle angle).

Yup, that's why sometimes the car will behave strangely if it doesn't use throttle-modulation during transition from spool to steady-state. My rule of thumb is usually ignore throttle cuts unless they are >25% dip

 

[totalone]

Looks alright. Bump up FF to 45, Enable bit 1, Set boost safety to 23.

Next log, start in 3rd gear at 2000 rpm, WOT to redline, upshift and let off after couple seconds.

Need to get ECU_PSI up so trims improve and timing cleans up.

Keep it at map4? To make those adjustments?

 

[ColonelAdama]

Keep it at map4? To make those adjustments?

Yes

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