I had the 90mm FRPP TB on my car with my BOSS intake and the throttle response was out of this world quick!!!!!!! It was "violent". Super snappy right off the go pedal. My tunes from another vendor were full of surging and hanging throttle while driving BUT as said, the throttle response was siiiiiiiiiick!!!!
If I could find a TB that gave me the crazy snap in throttle response without ill driving manners , I'd spend the $550 easily JUST for the violent throttle response.
So you took the TB off? Did you try it with Shaun's tune?