Going on boost soon and I have an NST underdrive pulley, just wanted to know if anyone had any problems using it while on boost. I still have the stock pulley and needed to know before I get to installing the kit

 

i would not change the pullies when putting more stress on the motor just my opinion. I would go stock pullies, i have stock lightweight crank pully on my turbo thats about it.

 

I Had a lightweight, stock size crank pulley for a almost as long as i owned the car. As soon as it was boosted and I put on a lightweight flywheel, I no longer liked how quickly the rev's dropped and I felt like it negatively affected some very fine points of driveability. Certainly nothing unmanageable, just a personal preference.