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Русский шпион Русский шпион is offline
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Posts: 5
Join Date: Oct 2017
Car: Z4sdrive35is
Default JB4 adjustments for N54 DCT cars - 10-24-2017, 08:00 AM

Hi guys.
I have Z4 sdrive35is DCT transmission with JB4.
When I go WOT on speed about 60 miles/hr the car shifts back to 4th, sometimes 3rd gear and when it just starts to pull ( the gears are fully engaged already), suddenly a boost swings occurs , one or two waves 10-18 PSI, car stalls for the moment, then pulls normally with 16 PSI of boost, and upshifts without a problem.
It happens in all JB4 maps, except map 0 (OEM map 8 PSI boost max).
It happens with all driving settings , like sport and sport + with traction off...or just traction off..
It happens when I downshift it manually and then slam my accelerator...
It does not happen if I accelerate, but do not go WOT.
It does not happen when I go WOT on a 1 gear and car does not have to downshift.
So question is... what is it and how it can be fixed?
Custom tune of JB4?
If it is a "traction control" intervention how can I turn it off completely?
Maybe it needs a transmission reprogrammation/tuning to help it handle more powerful engine by not shifting down to 3rd gear from 7th?

Last edited by Русский шпион; 10-24-2017 at 12:42 PM.. Reason: more details about the issue.
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