jb4 2step doesnt hold set rpm

AK135i

Corporal
Dec 13, 2016
117
32
0
31
Anchorage, Alaska
Ride
2010 135i
You have to click on bits and select the appropriate bit to output the extra fuel related data. It's bit5 and FUD will result in 32 after setting it.

Just email me the file, or the full file name, as that also has the DME version required.
I'm using an iPhone, I don't have a windows computer either to connect it with a data cable. I'm sorry but I'm not quite following what "bit" means. When I select the FUD box it just opens the lettered keyboard.
 

AK135i

Corporal
Dec 13, 2016
117
32
0
31
Anchorage, Alaska
Ride
2010 135i
You have to click on bits and select the appropriate bit to output the extra fuel related data. It's bit5 and FUD will result in 32 after setting it.

Just email me the file, or the full file name, as that also has the DME version required.
Figured it out my bad.
 

AK135i

Corporal
Dec 13, 2016
117
32
0
31
Anchorage, Alaska
Ride
2010 135i
You have to click on bits and select the appropriate bit to output the extra fuel related data. It's bit5 and FUD will result in 32 after setting it.

Just email me the file, or the full file name, as that also has the DME version required.
Enable the bank2 fuel trim logging under the FUD options, set meth safety mode = 1 (so it ignores history timing for its mapping), and lets see if we can get to the bottom of the fueling issue.

We may also need to adjust the fuel scalar down in the BEF. Email me the file you have loaded and I can tweak that for you.
I had a mix of good logs and poor logs, best compared to the worst.
 

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Terry@BMS

Sergeant
Platinum Vendor
Jan 23, 2017
464
380
50
Both seem about right to me for 90 octane. I would ensure the fuel scalar is set to 1.0 in the BEF but other than that I think the timing drop in higher gears is octane induced. Bank to bank fuel trims are lined up so meth distribution isn't an issue. The only other thing you could do if you wanted to be more aggressive is desensitize the knock sensors....

031017_0757.jpg

031017_0757-jpg.2804
 
Last edited:

AK135i

Corporal
Dec 13, 2016
117
32
0
31
Anchorage, Alaska
Ride
2010 135i
Both seem about right to me for 90 octane. I would ensure the fuel scalar is set to 1.0 in the BEF but other than that I think the timing drop in higher gears is octane induced. Bank to bank fuel trims are lined up so meth distribution isn't an issue. The only other thing you could do if you wanted to be more aggressive is desensitize the knock sensors....
031017_0757-jpg.2804
thanks for the response, would the next best step be to get a custom bef?
 

Terry@BMS

Sergeant
Platinum Vendor
Jan 23, 2017
464
380
50
Because you are relying on methanol for octane you're using the progressive meth map, boost is mapped on meth flow, and during a NLS the JB4 cuts meth flow momentarily so you don't grenade your intake manifold. So this is all normal behavior for the situation.

I don't see any benefit/need for custom tuning on this application. If you want to run it more aggressively you can do that. But on 90 octane I don't think I would. I would update to the latest v32.6 firmware though as we made some methanol mapping changes that may benefit you.

031017_0820.jpg
 

AK135i

Corporal
Dec 13, 2016
117
32
0
31
Anchorage, Alaska
Ride
2010 135i
Because you are relying on methanol for octane you're using the progressive meth map, boost is mapped on meth flow, and during a NLS the JB4 cuts meth flow momentarily so you don't grenade your intake manifold. So this is all normal behavior for the situation.

I don't see any benefit/need for custom tuning on this application. If you want to run it more aggressively you can do that. But on 90 octane I don't think I would. I would update to the latest v32.6 firmware though as we made some methanol mapping changes that may benefit you.

View attachment 2805
i updated the firmeware and also changed my map 12 settings to 3000 and the car is running much better now, I was wondering of you could explain to me in a simplified version of what new options there are regarding the methanol system, i set FUA to 60 and it stopped all meth flow, i don't quite understand the description you let under the firmware update.
 

Terry@BMS

Sergeant
Platinum Vendor
Jan 23, 2017
464
380
50
The FUA=60 is a new PWM methanol control scheme.. I don't think you need that since you'll want the maximum possible meth flow due to the low octane. But if you were running larger nozzles or direct port meth and wanted to better dial in the meth profile you'd use the 60 and the fuel by RPM settings on the user adjustment page.
 
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Reactions: AK135i

AK135i

Corporal
Dec 13, 2016
117
32
0
31
Anchorage, Alaska
Ride
2010 135i
Is there any way to make the 2-3 gear shift less notchy? compared to 3-4 and 4-5 shift its the slowest and most notchy shift, maybe a short shift kit would help I occasionally miss 3rd? It feels like im tapping the breaks mid shift while NLSing from 2nd to 3rd, 3rd to 4th is better, and 4-5th gear is perfect and seamless shift.