JB4tech.com - International Turbo Tuning Discussion
335i_GC 335i_GC is offline
New Member
Posts: 3
Join Date: Sep 2019
Car: bmw 335i
Default Overboosting? - 09-12-2021, 01:57 PM

hello guys I'm quite new to this forum but been on the bmw scene for a few years .

I iwn a 2006 335i with uprated turbos fbo and meth running jb4.

I've had the car dynoed at 680bhp last year.
First had a major boost leak so had metal outlets fabricated
The car has been checked now with no boost leak issues .

I had it dynoed last week and I'm hitting 430. The guy says it seems as if I'm overboosting then its shutting down top end of the rev range ..

I've done a log which I will post .

Just trying to get down to the bottom of the lost power..

Kind regs

Attached Files
File Type: csv 3rd gear pull yt56yay.csv (58.3 KB, 38 views)
Reply With Quote
TermiT TermiT is offline
New Member
Posts: 6
Join Date: Sep 2020
Car: BMW E92 335i
Default 09-12-2021, 03:04 PM

Log removed incorrectly
Reply With Quote
Steve @ BMS/Fuel-It!'s Avatar
Steve @ BMS/Fuel-It! Steve @ BMS/Fuel-It! is offline
Posts: 21,116
Join Date: Oct 2012
Car: 135i
Default 09-13-2021, 10:12 AM

You need to adjust your duty biases manually since wastegate adaption is disabled. Once those are dialed in, then you can start cranking up the boost as you're not going to make that kind of power on map 2.

JB4 Duty Bias FF Tuning Info - N54Tech.com - International Turbo Racing Discussion

Click on our banner to visit our website!
Video of our Stage 2 LPFP upgrade installation.

BMS products labeled for use only in competition racing vehicles may only be used on competition racing vehicles operated exclusively on a closed course in conjunction with a sanctioned racing event, in accordance with all federal and state laws, and may never be operated on public roads/highways.
Reply With Quote

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

vBulletin Skin developed by: vBStyles.com
Copyright 2007 - 2022, JB4tech.com