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Default Hiccups with 340i JB4 - 03-18-2019, 10:35 AM

Hey guys

My brother has a 2018 340i MT and says hes experiencing what feels like excessive turbo lag and bogging immediately after shifts during WOT.

He has a JB4 map 2, CLDP, BMS billet intake, and is running 91 octane.

From the logs he sent, his throttle is closing up. Attached are logs on map 0 and 2 from 2k-5k rpm

Any help would be much appreciated; thanks in advanced!
Attached Files
File Type: csv 2019-03-17 19_52_06 Map-0.csv (17.1 KB, 72 views)
File Type: csv 2019-03-17 19_52_45 Map-2.csv (19.4 KB, 67 views)
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Payam @ BMS's Avatar
Payam @ BMS Payam @ BMS is offline
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Default 03-18-2019, 11:05 AM

Both logs look normal to me. I'd go down to map 1 though if using 91 octane.
Having a few timing drops. Throttle closure is normal in the beginning to regulate boost.
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HitmanHearns HitmanHearns is offline
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Car: 2016 340i
Default 03-18-2019, 04:36 PM

I agree with payam. For 91 stay on Map 1 no matter what. Try adding some e85. Do a 12 gallon 91 octane and 3 gallon e85 mixture and record some logs.

I've experimented for almost 3 years on my B58. e85/octane boosters really help us (I am stuck with 91 octane as well).

2016 340i M-Sport |JB4|ER DNPIPE|BMS Intake|
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Got Boost?'s Avatar
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Default 03-19-2019, 10:00 AM

Thanks for your help guys. I'll relay the message
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