RB Turbo 19t's JB4 Map

[rebel876]

I just upgraded my turbo from stock to RB 19t's. Just wondering what map I can "safely" run/start on until I get the car tuned? Car was running map 2 before the upgrade and I typically try to run an e40 mix most of the time but may do full 93 oct occasionally. Car is a 2007 335i coupe.

Supporting mods
- 7.5 Race intercooler
- ARM ********* to stock *** back
- Tial BOV
- Fuel it Bucketless LPFP
- Index 12 injectiors
- New HPFP
- MHD with JB4 BEF with Race bin file.

[Steve @ BMS/Fuel-It!]

Set your JB4 up for the hybrid turbos and start with a log on map 1.

Here's a link for the hybrid turbo thread.

https://www.jb4tech.com/forum/model-specific-engine-tuning-modification-discussion/n54/5836-jb4-n54-hybrid-turbo-setup-directions

[rebel876]

Steve @ BMS/Fuel-It! Followed the steps, car keep switching to MAP 4. On Map 5 car drives ok but not as powerful. Logs attached.

[Steve @ BMS/Fuel-It!]

That doesn't look like you followed the tuning instructions to me. Duty biases are all still set to 50, etc.

Per the instructions

[rebel876]

Steve @ BMS/Fuel-It! Hi Steve here is another datalog not sure what happened with the 1st but the values are saved. Same problem, on Map 2 or 6 car will revert to map 4. But on map 5 seems to drive without an issue. It seems like it only changes the map to 4 under low speeds say 30 mph then if i give about 70% throttle the car is sluggish to build boost, then i'll see the indicator flash to show it switched maps. Also i cannot set my upper boost above 21 as im still on the stock map sensor ( 3.5 on its way) so that is why from 4500 rpm up the boost setting is at 21. I also attached screen shots of JB4 Settings.

[Steve @ BMS/Fuel-It!]

Hi,

No need to post those images, I can see all that in the logs.

None of your runs are at WOT so the Jb4 can't learn. Set your FF to 50 and do a couple WOT runs starting in 3rd gear at 2K rpms and take it to redline on a safe private track.

[rebel876]

Steve @ BMS/Fuel-It! Changed the ff Value to 50, no more switching to map 4. I also did some reading up and found this site https://bmwtuning.co/bmw-n54-data-logging-with-jb4/ that gives a great overview of the JB4 logging param's. I now see that the "last safety" 1 means the maps were switching because of overboost. I assume this is why you had me lower the duty to get the boost under control? I attached 2 new logs. Car felt great with duty at 50, spiking at 20 then holding around 17 to 18 PSI until the IC hose decided to come loose. AFR seems ok? but i see fuel trim in the high 40's to low 50's. Perhaps my e40 mix is too much? (Dont have a gauge to tell just blending based off tank capacity)

[Steve @ BMS/Fuel-It!]

That looks better, set your FOL to 90 to get your trims down a bit.

[rebel876]

Steve @ BMS/Fuel-It! Thank you sir! one last thing and i'll stop bothering you. I got my 3.5 bar map today. After installing i'll adjust tmap setting from 0 to 1 and adjust the map 6 boost settings to what is reflected. Do i need to change the ff back to 100 or leave it at 50?. How do i get to 22 PSI steady? that's as far as i want to push these turbos for longevity? is it just a matter of small changes to the ff wastegate and adjusting fol? while maintaining the AFR?

[Steve @ BMS/Fuel-It!]

Correct and still change the FOL and FF as directed.

Then you can log and we can go from there.

Stick with map 2 for now. One step at a time, don't over complicate it and do not play with map 6 if you don't know how to read logs, etc.

[rebel876]

Steve @ BMS/Fuel-It! 3.5 tmap installed. tmap sensor setting changed to 1, ff set to 50, fol set to 90 datalog attached.
Fuel trims are down and afr seems a litter richer at wot.

[Steve @ BMS/Fuel-It!]

Looks like it's getting better! Do a few pulls on map 5 next.

[rebel876]

Steve @ BMS/Fuel-It! Map 5 logs, the log file ending _1326 looks like it pulled timing? ( i forgot to turn off the traction control) the second log with DCT off feels like map 2 but this time without triggering the safety, but seems like it pulled timing twice in 4500 to 5000 rpm range in 4th and 5th gear?

[Steve @ BMS/Fuel-It!]

Looks pretty normal but cylinder 4 has a tendency to randomly pull timing.