^^try anything 2.5" to 3" piping and you will get some of the exhaust note back alongside better torque. again, backpressure is your going to be your worst enemy because you are adding a turbo to an originally n/a car
60mm and up is going to be perfect. 55mm is probably going to be wayyy too restrictive so I would stay away from that. You need to remember that this car came stock w/o a turbo so its originally relying on backpressure. going to 60mm is going to create a less restritive flow. so yea, you will be ok with this
Turbos have the best hp gain per dollar, so I'll be considering getting one in the future. I can pass emissions with a strait pipe here in NY through a connection...but I'm considering a 3" high flow cat just for the sake of passing a visual inspection & making a little less noise. To those who have a 3" high flow cat, which one do you use? Which one's the best?