F1X N55 Tuning Woes

KClemente

Specialist
Nov 26, 2019
84
So I've been tuning N54's for a few years now and finally got around to trying to tune my brother in laws F10 535 PWG. For some reason, I just cant get boost above 10 psi and the log overall is just messy. I've changed basically all the basics and nannies that I could think of. Feel free to look at the bin and corresponding xdf for his software version.

I've used the JB4 BEF as the base and tweaked the boost maps. Don't worry, load ceiling (super knock) will be changed as that was just a tester.

Whats interesting is that Tq Lim 1/2/3 spike up to 1048576 and drop down to 1 throughout the entire pull.

Also 70% WGDC @ 9 PSI actual (10 PSI target) near redline? He's got catless downpipes and a simple BMS intake installed.

 

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JPuehl

Lurker
Jul 24, 2019
19
Greater Seattle area
Just curious, are you using the JB4 BEF as a stand alone tune? I don't think that's how it's meant to be used. I use it with my JB4 and have no problem with boost (and over shooting target, lol).
 

KClemente

Specialist
Nov 26, 2019
84
@JPuehl
It was based off of the BEF maps, but I changed everything that would affect flash only boost targets. I was hitting a value of 1 on Tq Lim 1/2/3. I sort of remedied it now and boost climbed to 13 psi. Small increase in target but still not where I want it.

I do have a JB4 ready to pop in but I have to resolder the diode and convert back to integrated instead of the now unsupported ISO mode.
 

JPuehl

Lurker
Jul 24, 2019
19
Greater Seattle area
@JPuehl
It was based off of the BEF maps, but I changed everything that would affect flash only boost targets. I was hitting a value of 1 on Tq Lim 1/2/3. I sort of remedied it now and boost climbed to 13 psi. Small increase in target but still not where I want it.

I do have a JB4 ready to pop in but I have to resolder the diode and convert back to integrated instead of the now unsupported ISO mode.
Interesting, so it's no longer recommended to "cut the diode" on the older boards? I just bought a new board a couple of months ago and assumed it didn't have the diode and just installed it and am using it without issue.
 

KClemente

Specialist
Nov 26, 2019
84
Interesting, so it's no longer recommended to "cut the diode" on the older boards? I just bought a new board a couple of months ago and assumed it didn't have the diode and just installed it and am using it without issue.
Yep, classic Terry, no explicit instructions but there’s a post on page like 50 of the ISO firmware thread on N54tech.

N55 JB4 is so much weirder and information is so scattered. PWG F series need the diode to run integrated mode as I guess Terry was having issues with ISO mode so he scrapped that project.

Your board (V2) has new isolated power and ground circuitry because people kept on destroying the ground circuit for the tmap sensor in the dme. (Accidentally touching the datacable usb to a 12v post in the engine bay)
 

JPuehl

Lurker
Jul 24, 2019
19
Greater Seattle area
Yep, classic Terry, no explicit instructions but there’s a post on page like 50 of the ISO firmware thread on N54tech.

N55 JB4 is so much weirder and information is so scattered. PWG F series need the diode to run integrated mode as I guess Terry was having issues with ISO mode so he scrapped that project.

Your board (V2) has new isolated power and ground circuitry because people kept on destroying the ground circuit for the tmap sensor in the dme. (Accidentally touching the datacable usb to a 12v post in the engine bay)
"Yep, classic Terry," <--- lol

I was told to change the power supply with the new board, just wasn't told why.
 

KClemente

Specialist
Nov 26, 2019
84
"Yep, classic Terry," <--- lol

I was told to change the power supply with the new board, just wasn't told why.
How’s your car on the auto cross and or track? Thinking about taking mine but I wanna put in a baffled oil pan before really winding it out
 

KClemente

Specialist
Nov 26, 2019
84
The limiter is for guided gear protection. The car needs XHP to remove torque limiters in the TCU. Also, I would recommend removing the jb4.
Hm interesting, I had a hunch for that. And how come I shouldn’t install the JB4? I use it on my N54 pushing 30 psi right now with no issues.

N55 load targeting is so different yet so similar to N54 so when I command 187 load and only get an actual of 140 load it makes me wanna install the JB4, plug some numbers in and call it a day.

Maybe i’m just too used to tuning N54’s :sleeping:
 

all4bspinnin

Corporal
Jun 12, 2017
166
The N55 is extremely complex on the back end and a lot of processes talk to each other. Putting an archaic tool like a jb4 disrupts everything. Lying to the ecu is never the correct way to do it. Hell, I was tuning TurboXS utec's back in 2005 with better control... yet here we are in 2020 :(

I dont understand the BMW community sometimes... we're the only platform with proper DME flashing support still using a piggy back. If you tried to do this on another platform (subaru, evo, gtr, infiniti, mazda) they would literally flame you off the forum lol.

Also, with the JB4 the logger is terrible. You cant see EGT, tmap voltage, maf, etc which are all extremely useful in the tuning process.
 
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Reactions: CNM135i

CNM135i

Specialist
Nov 14, 2018
56
JB4 really is Terry-ble...badabum... F-series drives SOOOO much smoother without that in the mix. But the PWG is a BITCH to tune. I have more than +90 map revisions from three different tuners and were are not there yet.
 

KevinC39

Corporal
Jun 27, 2017
217
I have more than +90 map revisions from three different tuners and were are not there yet.
Seriously? 90+ and still not right? That's discouraging to hear. I have the Speedtech kit on a PWG E Series car. I'm on revision 9 and it's still not right either. I had even been thinking about trying a new tuner just to get some fresh eyes and advice on it.
 
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all4bspinnin

Corporal
Jun 12, 2017
166
JB4 really is Terry-ble...badabum... F-series drives SOOOO much smoother without that in the mix. But the PWG is a BITCH to tune. I have more than +90 map revisions from three different tuners and were are not there yet.
Welcome to owning a PWG. They are a pain in the butt. Especially the stock turbo ones because you have to hear the owners moan about how they got smoked by a stock b58. lol
 

houtan

Sergeant
Nov 2, 2017
306
Seriously? 90+ and still not right? That's discouraging to hear. I have the Speedtech kit on a PWG E Series car. I'm on revision 9 and it's still not right either. With the winters here, I run snow tires so I can't log and then with my tuners' often slow response time I don't get many revisions during the summer. It's frustrating. I had even been thinking about trying a new tuner just to get some fresh eyes and advice on it.
Any logs?
 

JPuehl

Lurker
Jul 24, 2019
19
Greater Seattle area
How’s your car on the auto cross and or track? Thinking about taking mine but I wanna put in a baffled oil pan before really winding it out
The car does well, been having fun with it for the past 5 years, well maybe 4 since I've only done 1 auto-cross event so far this year and that was in February. I don't think you'll need a baffle. I have a friend that has been tracking his 135i/N55 and haven't had an issue with oil pressure. I think we both agree that a better solution might be an Accusump rather than trying to figure out a baffle that would work. The JB4 was probably not a good addition for auto-cross since it's not as predictable as a stand-alone tune would/should be. Predictability is nice to have when racing.
 

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