dude, unless you get a return style fuel system, your probably always going to have that hiccup. i did the pprv delete, had it retuned and made it very clear to my tuner what was going on, and every now and again if I shift too fast it will still hiccup. if you have a fuel pressure gauge you can see whats happening. when you let off the gas all the way - shift - and get back in to it full throttle very quick like, you will notice that the fuel pressure drops pretty significantly for a split second. that split second of 20 to 30ish psi going back in to full boost = an ultra lean condition that causes the car to buck. the pprv delete helps, as did the retune... but its still there. because of this, my next project is going to be either a greggs performance or lethal performance return system w/ rails, 60 lb injectors, and an sct baf maf (since it has to be retuned anyway). that will eliminate my hiccup problem and give me a fuel system that will support what i want to do in the future.