Overboosting?
 

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

Wayne

Log removed incorrectly

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