Does anyone have any experience with the n75 valve on a 2.7t, the one where it increases boost psi 1-3?

 

I assume you are referring to the N75 "race" (I believe the suffix is H?) valve.

I have one and currently have it uninstalled. I've found the stock valve to perform better after some back to back testing.

No experience on the 2.7T, if you have an S4 you might want to venture to those forums instead of the A4 section.

 

I've heard bad things about that valve. Most tuners I've talked to about it say to stay away from it.

 

Probably because all it does is increase the already large torque spike of the K03/4. I didn't notice any increase in actual boost.

I found it to push boost onset slightly back with a less smooth delivery of power. I switched back to the original valve and found power to be much smoother.