The fact is you have over boost problems and i am telling you how to fix it .... Dont you think i have donre the same thing to my own first car ?? I did the same thing  your doing years ago .. many many years ago. I did the same stuff to my car you are doing right now and I had the same problems. The fact is, the acuator is too strong for the factory N75 and the hoses going to the N75 have to be 3/8" DIA. The suply hose going to the N75 has to come from the Turbo housing.... not the manifold.

The fix will be a Factory acuator . I have some WG acuators in my shop and you can have one for free if you want. The factory one does not cause boost creep or boost drop if adjusted correctly. I am trying to save you a lot of time a fustration .... the ball is in your court ...good luck


Lee

Ok, how can you set 7-10 psi on a 14psi actuator? You can't the base pressure on a 14psi actuator with  0 DC is 14psi.. so telling him to set it correctly to 7 psi is just nonesense, No point in telling him what to do if its not physically possible to do it!

And the reason an uprated actuator is used is because the pressures inside the turbine housing blow the stock 7 psi actuator open, Ideally a flat based 10 psi one would have been used but it wasn't available at the time and TBH it wouldn't make any difference, whether you run 21psi at 30% DC or 60% DC it's still 21psi regardless of the base actuator pressure.

I can assure you even a new OEM actuator will not hold boost at high RPM on this turbo as the wastegate will be blown open...

yes, wont make any difference as they are running perfectly happily at 350-400 bhp with no issues..

Issue is the A4 BFB maps aren't fully defined and therefore it is very hard to actually get it right, unlike the BAM me7.5 which i can happily make run 24psi boost with no issues.