Well the biggest thing you will noticed is the throttle response (the tune gets rid of accel and deccel lag) and a little increase in sound. I know when I got my intake on i hear a lot more sound, you won't noticed much with the catted test pipe. If you are lucky, you'll see +15HP and +20ft*lb. I think this are high as you will still have a cat especially since it's the 150hp motor and not the 170hp. No matter what you do without a turbo (and N02 technically) it will never make very much power... for all intensive purposes, your 0-60 time won't change.